Maria Ines Baragatti - CURSO COMPLETO DE VARIABLE COMPLEJA - UNLP
July 13, 2022 | Author: Anonymous | Category: N/A
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F_TVB FBNYMOXB S@TG@DMO FBNYMOE@ _AMY N`k. N`rî` Gaçs D`r`k`ttg
N`tonàtgf` H y H0
N@XONÀXGF@ H y H0
Nöhumb G5 @aàmgsgs ho S`rg`dmo Fbnpmoe`
_agh`h 9
Aõnorbs Fbnpmoebs N`k. N`rî` Gaçs D`r`k`ttg
♣ Aõnorbs
fbnpmoebs. Koaor`mgh`hos
♣ _a aõnorb fbnpmoeb os ua p`r brhoa`hb ho aõnorbs ro`mos (`,d) Fbnõanoato utgmgz`nbs m` motr` z p`r` gahgf`r ua fbnpmoeb y osfrgdgnbs5
z > (`,d)
♣ Om fbaeuatb ho tbhbs mbs aõnorbs fbnpmoebs mb hosgka`nbs fba m` motr` F. ♣ M` prgnor` fbnpbaoato hom fbnpmoeb z > (`,d) so hoabnga` fbnpbaoato ro`m ho z y m` gahgf`nbs5 ` > To(z)
p`rto ro`m ho z b
♣ M` sokuah` fbnpbaoato hom fbnpmoeb z > (`,d) so hoabnga` p`rto fbnpbaoato gn`kga`rg` ho z y m` gahgf`nbs5 d > Gn(z)
gn`kga`rg` ho z b
♣ Vg m` prgnor` fbnpbaoato ho ua fbnpmoeb os gku`m ` forb , os hofgr z quo z os ua aõnorb gn`kga`rgb purb.
> (9,d) hofgnbs quo
♣ Om fbnpmoeb z puoho roprosoat`rso fbnb ua puatb hom pm`ab ho fbbrhoa`h`s (`,d) b fbnb ua voftbr ho fbnpbaoatos (`,d).
y
z
d `
x
♣ Gku`mh`h ho aõnorbs fbnpmoebs Hbs aõnorbs fbnpmoebs z0 > (`0,d0) y y sus p`rtos gn`kga`rg`s.
z4 > (`4,d4) sba gku`mos sg fbgafghoa sus p`rtos ro`mos
Vgndömgf`noato osfrgdgnbs 5
z0 > z4 ⇘ ZTo (z0) > To (z4) y Gn(z0) > Gn (z4)^ ⇘ Z`0 > `0 y d0 >d4^ 0
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0
∃ @ftgvgh`h 05 H`hbs mbs fbnpmoebs z0 > (6t -4 , 8s +;) y z0 > ro`mos, l`mm`r mbs v`mbros ho s y t p`r` quo z0 > z4
(8s -4t , s + t ) sgoahb s y t hbs aõnorbs
♣ Vun` y prbhuftb ho h o fbnpmoebs H`hbs mbs fbnpmoebs z0 > prbhuftb oatro ommbs fbnb5
(`, d) y z4 > (f, h) , so hocgaoa m`s bpor`fgbaos ho sun` y
z0 + z4 > (` , d) + (f , h) > (` + f , d + h) z0 . z4 > (` , d) . (f , h) > (`f ‖ dh , `h + df) ⊟
Bdsorv`fgbaos5
0- M` sun` y prbhuftb ho hbs aõnorbs fbnpmoebs t`ndgça sba aõnorbs fbnpmoebs. 4 - Om fbnpmoeb (9,9) os om omonoatb aoutrb ho m` sun` puos
(`,d) + (9.9) > (`,d)
6- Om fbnpmoeb (0,9) os om omonoatb aoutrb hom prbhuftb puos (`,d) . (0.9) > (`,d) 8- M` sun` ho fbnpmoebs fbnpmoeb s oqugv`mo ` m` sun` ho sus fbnpbaoatos, pbr ommb so fbnpbrt` fbnb ua` sun` voftbrg`m.
z0 + z4
y
z0
z4
z0 + z4 > (` , d) + (f , h) > (` + f , d + h) x
?- Mbs aõnorbs fbnpmoebs fba p`rto gn`kga`rg` aum` so fbnpbrt`a fbnb mbs aõnorbs ro`mos puos, `pmgf`ahb m`s hocgagfgbaos ho sun` y prbhuftb, so bdsorv` quo 5
(` , 9) + (f , 9) > (` + f , 99)) y
(` , 9) . (f , 9) > (`f , 9)
fuybs rosumt`hbs so bdtgoaoa sun`ahb b numtgpmgf`ahb sus p`rtos ro`mos. Ybr ost` r`zöa os fbavoagoato fbasghor`r om sgston` ho aõnorbs ro`mos fbnb ua f`sb p`rtgfum`r hom sgston` ho aõnorbs fbnpmoebs y fbavoagnbs oa ghoatgcgf`r `m fbnpmoeb (`,9) fba om aõnorb ro`m ` y osfrgdgnbs ` > (`,9). Ybr oeonpmb5 9 > (9,9) , 0 > (0,9) , -0 > (-0,9)
∃ @ftgvgh`h 45 Eustgcgf`r quo m`s bpor`fgbaos ho sun` y prbhuftb ho fbnpmoebs kbz`a ho m`s sgkugoatos prbpgoh`hos 5
fbanut`tgv`5
z0 + z4 > z4 + z0
z0.z4 > z4.z0 4
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0
`sbfg`tgv` 5 Zz0 + z4 ^+ z6 > z0 + Zz4 + z6^ hgstrgdutgv` hom prbhuftb rospoftb ` m` sun`5
Zz0.z4 ^. z6 > z0 . Zz4 . z6^ Zz0 + z4^ . z6 > z0 . z6 + z4 . z6
♣ _agh`h gn`kga`rg` gn`kga`rg` Om aõnorb fbnpmoeb (9,0) so roprosoat` pbr Osfrgdgnbs 5
g y so hoabnga` uagh`h gn`kga`rg`.
g > (9,0)
∃ @ftgvgh`h 65 `) F`mfum`r
g4 > g . g > …… y fbnpmot`r om rofu`hrb
d) F`mfum`r
g6 > g4 . g
g4 >
8a 8a+0 8a +6 , g8 > g6 . g y `vorgku`r om v`mbr ho m`s m `s pbtoafg`s5 g , g , g
∃ @ftgvgh`h 85 H`hb om fbnpmoeb z > (`,d) , eustgcgf`r m` sgkugoato gku`mh`h y hohufgr quo z puoho oxpros`rso oxpros`rso oa m` cbrn` z > ` + g d .
(`,d) > (`,9) + (9,0) . (d,9)
♣ Cbrn` dgaöngf` ho ua fbnpmoeb Xoagoahb oa fuoat` om rosumt`hb ho m` `ftgvgh`h `atorgbr , bdsorv`nbs quo 5
z> (`,d) puoho oxpros`rso oa m` cbrn` z > ` + g d , ` m` quo so hoabnga` cbrn` dgaöngf` hom fbnpmoeb. Xbhb fbnpmoeb
∃ @ftgvgh`h ?5 H`hbs mbs fbnpmoebs oa cbrn` dgaöngf`
z0 > `0 + g d0 y z4 > `4 + g d4 , eustgcgf`r quo om
z . z > (` + g d ) (` + g d ) 4 0 g4 > -0 0 4 4 puoho ro`mgz`rso us`ahb m` prbpgoh`h hgstrgdutgv` y prbhuftb oa0 fuoat` toagoahb quo ♣ Fbnpmoebs Om fbnpmoeb
fbaeuk`hbs
` ‖ g d os om fbnpmoeb fbaeuk`hb ho z > ` + gd y mb gahgf`nbs z > ` ‖ g d
♣ Nöhumb ho ua
fbnpmoeb fbnpmoeb
> ` + g d , om aõnorb ro`m ` 4 + d 4 os om nöhumb ho z , mb gahgf`nbs z > ` 4 + d 4 y rosumt` sor m` hgst`afg` ho z `m brgkoa ho fbbrhoa`h`s. fbbrhoa`h`s.
H`hb om fbnpmoeb z
6
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0
∃ @ftgvgh`h 35
Honbstr`r quo
z . z > | z |4
∃ @ftgvgh`h ;5 H`hb om fbnpmoeb ab aumb z w > f + hg p`r` quo om om prbhuftb
♣ Tost`
> ` + dg , `vorgku`r `vorgku`r quç cbrn` hodo toaor toaor om fbnpmoeb z . w so` ua aõnorb ro`m.
ho fbnpmoebs5
H`hbs mbs fbnpmoebs
z0 y z4 , m` rost` z0 ‖ z4 os ua fbnpmoeb z6 t`m quo z0 > z4 + z6
∃ @ftgvgh`h `0 + g d0 , z4> `4 + g d4 y z6> z0 ‖ z4 , eustgcgf`r quo
z6 > (`0 ‖ `4) + g (d0 ‖ d4)
♣ Fbfgoato ho aõnorbs fbnpmoebs 5
z0 H`hbs mbs fbnpmoebs z0 y z4 ≩ 9 , om fbfgoato z os ua fbnpmoeb z6 t`m quo z0 > z4 . z6 4 ∃ @ftgvgh`h 75 `) Vg z> ` + g d os ua fbnpmoeb ab aumb, eustgcgf`r m` sgkugoato oqugv`moafg`5 oqugv`moafg`5 4 z . w > 0 ⇘ w > z / |z| |z| z ` + gd 0 d) L`mm`r m` p`rto ro`m ro`m y m` p`rto gn`kga`rg` hom fbnpmoeb fbnpmoeb z 6 > 0 > 0 z 4 ` 4 + gd 4 sba aõnorbs ro`mos ab sgnumtàao`noato aumbs.
, hbaho `4 y d4
♣ Cbrn` pbm`r b trgkbabnçtrgf` ho ua fbnpmoeb Vg z > (`,d) os ua fbnpmoeb ab aumb, pbhonbs hocgagr sus fbnpbaoatos us`ahb m`s fbbrhoa`h`s pbm`ros 5
y
d
` > r fbs μ , d > r soa μ hbaho r > | z | , y μ os om àakumb oatro om voftbr ho fbnpbaoatos (`,d) y om oeo x pbsgtgvb, nohghb oa soatghb pbsgtgvb (`atglbr`rgb) b oa soatghb aok`tgvb (lbr`rgb).
z r μ
`
x
Ybr mb t`atb tbhb fbnpmoeb ab aumb puoho oxpros`rso fbnb
z > ` + g d > r fbs μ + g r soa μ > r (fbs μ + g soa μ) y ost` õmtgn` so hoabnga` cbrn` pbm`r b trgkbabnçtrgf` ho z.
8
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0
♣ @rkunoatb y `rkunoatb prgafgp`m ♣ Vg μ os om àakumb ho gafmga`fgöa ho ua fbnpmoeb ab aumb, os hofgr z ≩ 9, t`ndgça mb sba mbs aõnorbs μ + 4jω fba j > °0, ° 4, ° 6…. . Om fbaeuatb cbrn`hb pbr tbhbs ommbs so hoabnga` `rkunoatb ho z y mb gahgf`nbs `rk(z).
♣ Om `rkunoatb ho z ≩ 9 quo s`tgsc`fo - ω = μ ≨ ω , so hoabnga` `rkunoatb b `rkunoatb prgafgp`m y mb gahgf`nbs @rk(z)
v`mbr prgafgp`m hom
⊟ Bdsorv`fgöa Y`r` hotornga`r om àakumb μ , `m quo nohgnbs oa r`hg`aos, hodo toaorso oa fuoat` m` rom`fgöa tk μ > d/` y om fu`hr`ato oa quo so oafuoatr` om fbnpmoeb. Os d`st`ato usu`m quo so hgk` quo 5 "sg tk μ > d/` oatbafos μ > `rftk (d/`)" y ost` oxprosgöa ab os sgonpro fbrroft` fu`ahb so protoaho l`mm`r om `rkunoatb ho ua fbnpmoeb, puos hodonbs rofbrh`r quo5 m` cuafgöa y > `rftk x , ho v`rg`dmo ro`m x , tgoao fbnb hbngagb om fbaeuatb ho tbhbs mbs aõnorbs ro`mos porb su gn`koa os om gatorv`mb `dgortb ( -ω /4 , ω /4) . Xoagoahb oa fuoat` quo sömb mbs fbnpmoebs fba p`rto ro`m pbsgtgv` tgoaoa prgafgp`m oatro -ω /4 y ω /4 , sömb p`r` ommbs puoho us`rso quo μ > `rftk (d/`)
`rkunoatb
Oeonpmbs
# Vg
z0 > 4 + 4g ⇔ tkμ0 > 4/4 > 0 ⇔ μ0 > @rk(z0) > `rftk 0 > ω /8 , puos To(z0) 1 9 @rk(z0) > ω /8 y
Ybr mb t`atb
`rk(z0) > {ω /8 + 4jω , fba j > °0, ° 4, ° 6….}
# Vg z4 > 4 - 4g ⇔ tkμ4 > -4/4 > -0 ⇔ μ4 > @rk (z4) Ybr mb t`atb
@rk(z4) > -ω /8
y
>`rftk (-0) > - ω /8 , puos To(z4) 1 9
`rk(z4) > { - ω /8 + 4jω , fba j > °0, ° 4, ° 6.}
# Vg m` p`rto ro`m hom fbnpmoeb os aok`tgv` y su p`rto gn`kga`rg` os ppbsgtgv` bsgtgv` oatbafos om `rkunoatb prgafgp`m ho hgflb fbnpmoeb os `rftk (d/`) + ω Vg z6 > -4 + 4g ⇔ tkμ6 > 4/-4 > -0 ⇔ μ6 > `rftk (-0) + ω > - ω /8 + ω > 6ω /8, lonbs sun`hb ω `m `rftk (-0) puos Ybr mb t`atb
@rk(z6) > 6ω /8
y
To(z6) = 9 y Gn(z6) 1 9 `rk(z6) > { 6ω /8 + 4jω , fba j > °0, ° 4, ° 6.}
# Vg m` p`rto ro`m hom fbnpmoeb aok`tgv aok`tgv`` os y su`rftk p`rto(d/`) gn`kga`rg` os aok`tgv` oatbafos om `rkunoatb prgafgp`m ho hgflbosfbnpmoeb - ω ?
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0 Vg z8 > -4 - 4g ⇔ tkμ8 > -4/-4 > 0 ⇔ μ8 > `rftk 0 - ω > ω /8 - ω > - 6ω /8, lonbs rost`hb ω `m `rftk Ybr mb t`atb
0 puos To(z8) = 9 y Gn(z8) = 9
@rk(z8) > -6ω /8
`rk(z6) > { -6 ω /8 + 4jω , fba j > °0, ° 4, ° 6.}
y
∃ @ftgvgh`h 095 L`mm`r om `rkunoatb y om `rkunoatb prgafgp`m ho mbs fbnpmoebs y ho mbs fbnpmoebs
z* > 6 ∔∔ g , z** > - 6 ∔∔ g ,
-z* , - z** , z*. z** , z*/z**, z* + z** , z* - z** , -z* - z**, -z* + z**
∃ @ftgvgh`h 005 Vg om fbnpmoeb z0 > r0 ( fbs μ0 + g soa μ0 ) os gku`m `m fbnpmoeb z4 > r4 ( fbs μ4 + g soa μ4 ) , honbstr`r quo sus nöhumbs sba sba gku`mos y quo sus `rkunoatbs hgcgoroa oa ua nõmtgpmb ho 4ω , os hofgr μ0 > μ4 +4jω , fba j aõnorb oatorb.
♣ Ybtoafg`s Y`r` f`mfum`r m`s pbtoafg`s a`tur`mos ho ua fbnpmoeb dgabngb ho Aowtba5
z > ` + gd puoho us`rso m` cörnum` hom
a! a ∔j ` (gd ) j j > 9 j ! (a ∔ j )! a
z > (` + g d) > ∐ a
a
porb os d`st`ato tohgbs` su utgmgz`fgöa. Ybr ommb os fbavoagoato f`mfum`r fu`mqugor pbtoafg` ho ua fbnpmoeb , oxprosàahbmb oa m` cbrn` pbm`r. Os nuy gatoros`ato bdsorv`r quo sg ua fbnpmoeb z so oxpros` oa cbrn` pbm`r y tgoao nöhumb r 4 4 y `rkunoatb μ oatbafos om fbnpmoeb w > z tgoao nöhumb r y `rkunoatb 4μ + 4jω puos5
z4 > r4(fbs μ + g soa μ )4 > 4
Tofbrh`r quo 5
4
soa(` + d) > soa ` fbs d + fbs ` soa d fbs(` + d) > fbs ` fbs d - soa ` soa d
4
> r Zfbs μ + 4g fbs μ soa μ - soa μ ^ > > r4 Z (fbs4 μ - soa4 μ) + g 4fbs μ soa μ^ > 4
>r
` > d oatbafos soa (4`) >.............................. fbs(4`) >............................... sg
Z(fbs(4μ) +g soa(4μ)^ 4
4
4
pbr mb t`atb |z | > r y `rk(z ) > 4μ + 4jω fba j aõnorb oatorb , bdsorv`r quo ost` rom`fgöa oatro mbs `rkunoatbs ho hbs fbnpmoebs gku`mos cuo honbstr`hb oa m` `ftgvgh`h 00.
z6 > r6 Zfbs (6μ) + g soa(6μ)^
T`zba`ahb oa cbrn` sgngm`r puoho honbstr`rso quo 5 y utgmgz`ahb gahuffgöa fbnpmot` puoho honbstr`rso quo
5
3
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0
za > ra Zfbs (aμ) + g soa(aμ)^ , a ∌ A |za| > |z|a y `rk(za) > a `rk z
Ho hbaho so hosproaho quo5
Fbnoat`rgb @atos ho `a`mgz`r m` r`îz fu`hr`h` ho ua aõnorb fbnpmoeb os fbavoagoato l`for ua fbnoat`rgb sbdro m` ofu`fgöa ho v`rg`dmo ro`m x4 + 0 > 9 , quo s`donbs ab tgoao sbmufgöa oa om fbaeuatb ho aõnorbs ro`mos puos hospoe`ahb so bdtgoao x > ° ∔ 0 . ²Xoahrà sbmufgöa oa om fbaeuatb ho aõnorbs fbnpmoebs2 Y`r` fbatost`r poasonbs quo x os ua fbnpmoeb osfrgdgrso
` + gd , ho hbaho m` ofu`fgöa `atorgbr puoho
(` + gd)4 + 0 > 9 y ro`mgz`ahb m`s bpor`fgbaos gahgf`h`s bdtoaonbs
(`4 - d4 + 0) + g 4`d > 9 , ho hbaho `4 - d4 + 0 > 9 (0) y 4`d > 9 (4) Ho (4) so hosproaho quo
` > 9 ö d > 9 . 4
Vg ` > 9 , roonpm`z`nbs oa (0) y bdtoaonbs - d + 0 > 9 , ho hbaho d > 0 ö d > -0 , 4 pbr mb t`atb x > 9 + g > g y x > 9 - g > - g sba sbmufgbaos ho m` ofu`fgöa x + 0 > 9
d > 9 , roonpm`z`nbs oa (0) y bdtoaonbs `4 + 0 > 9 , quo aabb tgoao sbmufgöa. 4 Ybr mb t`atb m` ofu`fgöa x + 0 > 9 tgoao sbmufgöa oa om fbaeuatb ho aõnorbs fbnpmoebs y sus sbmufgbaos sba 5 g y -g
Vg
Yrotoahonbs `lbr` pbhor rosbmvor m` ofu`fgöa `atorgbr sga toaor quo l`for t`atb tr`d`eb, os hofgr protoahonbs oafbatr`r om v`mbr ho
♣
∔ 0 , tbn`ahb `
-0 fbnb om fbnpmoeb -0 + g9
T`îfos 4
Vg quoronbs l`mm`r z hodonbs oafbatr`r ua fbnpmoeb w t`m quo w > z . Y`r` ovgt`r tr`d`e`r fba sgtu`fgbaos fbnpmgf`h`s fbnb oa om fbnoat`rgb `atorgbr, os fbavoagoato fbasghor`r ` z y ` w oa m` cbrn` pbm`r. Vupbak`nbs quo
z > w , z > r ( fbs μ + g soa μ ) y w > T (fbs ϟ + g soa ϟ )
|w| > T y `rk(w) > ϟ t`m quo w4 > z , p`r` ommb fbasghor`nbs m` gku`mh`h w4 > z ⇔ T4 (fbs (4ϟ) + g soa(4ϟ ) > r ( fbs μ + g soa μ ) ⇔ T4 > r y 4ϟ > μ + 4jω ⇔ μ + 4j ω T > r y ϟ > 4
Hodonbs l`mm`r
Ybr mb t`atb
μ + 4jω , fba j > 9, 0 + gsoa 4
μ + 4jω
z > w > r fbs
4
² pbrquç lgfgnbs ost` rostrgffgöa p`r` om aõnorb oatorb j2 ..................... ........................................ ........................... ........ ;
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0 Oa cbrn` sgngm`r puoho honbstr`rso quo 5 6
μ + 4jω , fba j > 9, 0, 4 + g soa 6
μ + 4jω
z > w > 6 r fbs
6
W pbr gahuffgöa puoho honbstr`rso m` sgkugoato oxprosgöa, fbabfgh` fbnb
cörnum` ho Ho
Nbgvro5 a
z>
a
+ μ + ω μ + ω fba j > 9, 0 , 4,….., (a ‖ 0) r fbs a4j , a4j gsoa
∃ @ftgvgh`h 045 F`mfum`r
z6, z , 6 z 8 z 6 sgoahb z > < ( fbs ω /? + g soa ω /? ) .
♣ Cörnum` ho Oumor jx
Os nuy soafgmmb honbstr`r quo m` cuafgöa c(x) > o , hbaho x os ua` v`rg`dmo ro`m , os sbmufgöa ho m` ofu`fgöa hgcoroafg`m hgcoroafg`m c ‗(x) > j c(x) y vorgcgf` c(9) > 0. Vg pbr btr` p`rto fbasghor`nbs m`s cuafgbaos os nuy soafgmmb bdsorv`r quo 5
u(x) > fbs x y v(x) > soa x ho v`rg`dmo ro`m x,
u'(x) + g v'(x) > -soa x + g fbs x > g (fbs x + g soa x) > g Zu(x) + g v(x)^ (#) Vg mm`n`nbs
k(x) > fbs x + g soa x oatbafos m` oxprosgöa (#) puoho osfrgdgrso k'(x) > g k(x)
Fbnp`r`nbs mbs rosumt`hbs bdtoaghbs fba c(x) y k(x) V`donbs quo os sbmufgöa ho jx c(x) > o c ‗(x) > j c(x) k(x) > fbs x + g soa x k ‗(x) > g k(x)
y vorgcgf` vorgcg f` c(9) > 0 k(9) > 0
Vg tbn`nbs j > g , m` sokuah` y torfor` fbmuna` hom hom fu`hrb `atorgbr `cgrn`a m` ngsn` fbs`, fbs`, p`r` quo tbhb so` fbasgstoato, hodorà sor c(x) > k(x) , pbr mb t`atb os r`zba`dmo hocgagr p`r` x v`rg`dmo ro`m m` sgkugoato oxprosgöa, oxprosgöa, quo so hoabnga` hoabnga`
cörnum` ho Oumor
og x > fbs x + g soa x ∃ @ftgvgh`h 065 Eustgcgf`r quo
♣
o-gx > fbs x - g soa x , fba x aõnorb ro`m.
Abt`fgöa oxpbaoafg`m
μ os om `rkunoatb ho ua fbnpmoeb z ≩ 9, pbr m` cörnum` ho Oumor s`donbs quo o > fbs μ + g soa μ , pbr mb t`atb tbhb fbnpmoeb ab aumb z ho nöhumb r y `rkunoatb μ so puoho gahgf`r z > r og μ , hoabnga`h` abt`fgöa oxpbaoafg`m hom fbnpmoeb Vg
gμ
<
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0
∃ @ftgvgh`h 085 gω /8
Osfrgdgr mbs fbnpmoebs z0> g , z4 > -0 , z6 > -4g , z8 > 6 , z? > 0 - g , z3> -4 o ω cbrn` oxpbaoafg`m
, z;> g ogω /8 oa m`
⊟ Gnpbsgdgmgh`h ho brhoa`r mbs aõnorbs fbnpmoebs fbnpmoebs 5
V`donbs quo h`hbs hbs aõnorbs ro`mos hgstgatbs `0 y `4 , so vorgcgf` quo `0 1 `4 b `0 = `4 . Ost` `cgrn`fgöa ab puoho l`forso oatro hbs aõnorbs fbnpmoebs y p`r` eustgcgf`rmb supbak`nbs quo mbs fbnpmoebs g y 9 puohoa brhoa`rso.
g 1 9 oatbafos g4 1 9, puos om prbhuftb ho hbs aõnorbs n`ybros quo 9 os n`ybr quo 9, pbr mb t`atb -0 1 9 4 # Vg g = 9 oatbafos g 1 9, puos om prbhuftb ho hbs aõnorbs noabros quo 9 os n`ybr quo 9, pbr mb t`atb -0 1 9 @nd`s supbsgfgbaos supbsgfgbaos abs mmov`rba ` m` rom`fgöa5 rom`fgöa5 -0 1 9 (*) - Vg sun`nbs 0 ` `ndbs ngondrbs ho (*) bdtoaonbs 9 1 0 (**) # Vg
- Vg `pmgf`nbs auov`noato m` prbpgoh`h ho prbhuftb ho aõnorbs n`ybros quo 9 ` (*), bdtoaonbs (-0)4 1 9, b 0 1 9 (***) Fbnb os gnpbsgdmo quo so funpm` (**) y (***) , oafbatr`nbs ua` fbatr`hgffgöa. Ybr mb t`atb pbhonbs `cgrn`r quo ”Mbs aõnorbs fbnpmoebs ab puohoa brhoa`rso sga prbhufgr ua` fbatr`hgffgöa oa m`s m`s prbpgoh`hos ho brhoa oatro aõnorbs aõnorbs ro`mos„
• Oeorfgfgbs
0- Oxpros`r mbs sgkugoatos aõnorbs fbnpmoebs oa m` cbrn` x + g y `) ( 0 + g ) 6
d) g6 + g0;
f) (4 + 6g) (6 ‖ 8g) -0
h) ¾ (0 + g) (0 + g- - Gn(z)
d) To(z) > Gn(gz)
o) | z | ≨ |To(z)| + |Gn(z)|
c)
(z )4 > z 4
f) To(z) ≨ | z | k) z .z >
z
4
h) Gn(z) ≨ | z |
`rk(( z ) > l) `rk
- `rk(z) `rk(z)
6- Vg z0 y z4 sba hbs fbnpmoebs ab aumbs, honbstr`r quo5 `)
z 0 + z 4 > z 0 + z 4
d)
z 0 . z 4 > z 0 . z 4
z 0 z 0 > sg z4 ≩ 9 z z 4 4
f)
7
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0
8- L`mm`r om nöhumb, om `rkunoatb y om `rkunoatb prgafgp`m y m` roprosoat`fgöa oxpbaoafg`m ho `) g
d) 0 ‖g
f) ‖6
h) ‖4 ‖ g
o) ‖4g
?- F`mfum`r `)
0?
(
6 ++ g )
d) (0 ‖ g)
09
0/4
f) g
0/6
h) (-4;)
3- L`mm`r m`s sbmufgbaos ho m`s sgkugoatos ofu`fgbaos 8
`) z
+ 0 > 9
4
d) z
6
‖ 4gz ‖4 > 9
f) z
‖0>g 6
;- Vg z0> ` ogμ , z4> d ogϟ fba ` . d ≩ 9 , eustgcgf`r quo5 `) Vg d) Vg f) Vg
- ω = μ + ϟ ≨ ω oatbafos @rk(z0 . z4) > @rk(z0) + @rk(z4) - 4ω = μ + ϟ ≨ - ω oatbafos @rk(z0 . z4) > @rk(z0) + @rk(z4) + 4 ω ω = μ + ϟ ≨ 4ω oatbafos @rk(z0 . z4) > @rk(z0) + @rk(z4) - 4 ω
4 z 0 + z 4
f)
z0 + z 4 ≨ z0 + z 4
4
(`yuh`5 us`r d)
4
4
4
d)
z 0 ° z 4 > z 0 + z 4 ° 4 To(z 0 .z 4 )
h)
z 0 ° z 4 ≯ z 0 ∔ z 4
7- Toprosoat`r kràcgf`noato mbs fbnpmoebs z quo vorgcgf`a m`s m `s sgkugoatos rom`fgbaos5 `) To(z) > 4 4
h) z
> z
k) |z| = |z ‖ 4g| e)
|z ‖ g| ≯ |z + 4|
d) ‖0 = Gn(z) ≨ 6
f) z > z
o)
c) ω /8 = @rk(z) = ω , | z | 14
z ∔ 4 1 0
l) |z| 1 Gn(z)
g) |z | ≨ |z ‖ 0| ≨ |z ‖ g|
j) |z| > To(z)
m) z
z > z ‖ z
4 09- Vg z9 os ua puatb gatorgbr ` m` furv` furv` ζ ζ ζ5 |z| > T , eustgcgf`r quo T z 9 os oxtorgbr ` ζ
09
Nöhumb G - _agh`h 9
N`tonàtgf` H y H0
N@XONÀXGF@ H y H0
Nöhumb G5 @aàmgsgs ho S`rg`dmo Fbnpmoe`
_agh`h 0
Cuafgbaos ho v`rg`dmo fbnpmoe` N`k. N`rî` Gaçs D`r`k`ttg
0- Cuafgbaos ho v`rg`dmo fbnpmoe` Vg ` tbhb aõnorb z ho ua fbaeuatb H ho aõnorbs fbnpmoebs mb rom`fgba`nbs fba ua aõnorb fbnpmoeb w , hofgnbs quo lonbs hocgaghb ua` cuafgöa ho hbngagb fbhbngagb F .
õagfb H y
Y`r` gahgf`r quo c os ua` cuafgöa ho H oa F , `abt`nbs
c5H z
↔ ↔
F ↔ ↔ w > c(z)
Vg c ostà oa m`s fbahgfgbaos `atorgbros, hofgnbs quo c os ua` cuafgöa ho v`rg`dmo fbnpmoe` . Vg z y w so osfrgdoa oa cbrn` dgaöngf` y supbaonbs quo w > c(z) puoho osfrgdgrso nohg`ato m` gku`mh`h5
z > x + gy , w > u + gv oatbafos
u + g v > c(x + g y) y pbr mb t`atb u y v , quo sba ro`mos, hopoahoràa ho m`s v`rg`dmos ro`mos x o y , os hofgr
u > u(x,y) , v > v(x,y) Oeonpmbs
0-
4-
c(z ) > z4 os ua` cuafgöa ho hbngagb F quo ` f`h` fbnpmoeb mb rom`fgba` fba su fu`hr`hb quo vorgcgf` 5 w > c(z ) > z4 > (x + gy)4 > x4 ‖ y4 + g 4xy ⇔ u(x,y) > x4 ‖ y4 y v(x,y)> 4xy k(z) > g / |z|4 os ua` cuafgöa ho hbngagb F ‖ {9} quo vorgcgf`5 w > k(z) > g / |z| 4 > g / (x 4 + y4) ⇔ u(x,y) > 9 y v(x,y) > 0 / (x4 + y4) 0
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 6-
l0(z) > `rk(z) ab os ua` cuafgöa, puos f`h` fbnpmoeb z ab aumb tgoao gacgagtbs v`mbros hom `rkunoatb, oa f`ndgb l4(z) > @rk(z) os ua` cuafgöa ho hbngagb F ‖ {9} puos om 9 os om õagfb fbnpmoeb quo ab tgoao `rkunoatb y f`h` fbnpmoeb tgoao ua õagfb `rkunoatb prgafgp`m.
8- V`donbs quo oa v`rg`dmo ro`m fbnpmoe` rosumt`hbs.
c ( x ) > x os ua` cuafgöa fba fba hbngagb Z9, ∑) , oa v`rg`dmo z ab os ua` cuafgöa puos p`r` f`h` fbnpmoeb z , su r`îz fu`hr`h` tgoao hbs x fbnb `quom aõnorb pbsgtgvb fuyb fu`hr`hb os gku`m ` x , `sî 8 > 4
Tofbrh`r quo oa v`rg`dmo ro`m so hocgao
5
∃ @ftgvgh`h 0 Gahgf`r om hbngagb nàs `npmgb y oxpmgfgt`r m` p`rto ro`m y m` p`rto gn`kga`rg` ho m`s sgkugoatos cuafgbaos5 `)
c 0 (z ) >
z To(4z )
d)
c 4 ( z ) >
4∔g 0∔ | z |
f)
c 6 ( z ) >
gz z
4- Mîngto ♣ Vo hoabnga` oatbrab ho r`hgb
r ho ua fbnpmoeb z9 `m fbaeuatb {z / |z ‖ z9 | = r} quo roprosoat` ua fîrfumb `dgortb foatr`hb oa z9 . Vg ` hgflb fîrfumb mo s`f`nbs om puatb z9 toaonbs mb quo so hoabnga` oatbrab rohufghb. z9
z9
Oatbrab rohufghb ho z9
Oatbrab ho z9
♣ Vg oa tbhb oatbrab ho z 9 l`y gacgagtbs puatbs portoaofgoatos ` ua fbaeuatb H, hofgnbs quo
z9 os ua puatb ho `funum`fgöa ho H.
♣ Vo`
z9 ua puatb ho `funum`fgöa hom hbngagb H ho c(z) , hofgnbs quo c(z) tgoao mîngto M fu`ahb z tgoaho ` z9 o gahgf`nbs mîn c(z) > M sî y sömb sî mîn c(z) - M > 9 z↔z9
z↔z 9
Fbnb |c(z) ‖ M| os ua` cuafgöa ` v`mbros ro`mos, s`donbs quo
mîn c(z) ∔ M
z↔z9
>
9 sgkagcgf` quo 5
p`r` tbhb aõnorb pbsgtgvb ο, pbhonbs oafbatr`r ua aõnorb pbsgtgvb θ, quo hopoaho ο, t`m quo | c(z) ‖ M | = ο p`r` tbhbs mbs z ho H quo vorgcgf`a 9 = | z ‖ z9 | = θ
@ftgvgh`h 45
∃
`) Eustgcgf`r us`ahb m` hocgagfgöa quo 5 d) _s`ahb `) eustgcgf`r quo 5
mîn c(z) > 9 ⇘ mîn c(z) > 9 z↔9
z↔9
z ↔ 9 ⇘ | z | ↔ 9 4
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0
@ftgvgh`h 65
∃
H`h`
c(z)
>
fbs
0 0 , fbnprbd`r quo mîn c(z) + g soa z↔9 |z| |z|
Osto oeonpmb nuostr` quo oa koaor`m
Α Xobron`
mîn c(z) ∔ 0 z↔9
≩
9
mîn c(z) >| M | ab os oqugv`moato ` mîn c(z) ∔ M
z ↔z 9
z↔z9
>
9
ho gatorf`m`fgöa (t`ndgça mm`n`hb hom s`ahwgfl)
Vg oa ua oatbrab rohufghb ho z9 mîn k(z) > mîn l(z) > @ oatbafos mîn z ↔z 9
> 0 y
z ↔z 9
z↔z9
so vorgcgf` quo c(z) > @
|k(z)|
≨
|c(z)|
≨
|l(z)|
y
@ftgvgh`h 85
∃
H`h` c(z) > u(x,y) + g v(x,y) y
mîn c(z) > M > M 0 + g M 4
z ↔z 9
⇘
z9 > x9 + g y9 , eustgcgf`r quo5 mîn
( x , y ) ↔( x 9 . y 9 )
u(x, y) > M 0 y
mîn
( x ,y )↔( x 9 . y 9 )
v(x, y) > M 4
Xoaor oa fuoat` m`s gahgf`fgbaos quo so h`a ` fbatgau`fgöa
⇔) Fbnb m` p`rto ro`m y m` p`rto gn`kga`rg` ho ua fbnpmoeb sba noabros quo su nöhumb , pbhonbs `cgrn`r quo5 9 ≨ |u(x,y) ‖ M0| ≨ |c(z) gatorf`m`fgöa so bdtgoao mb dusf`hb.
- M| y
9 ≨ |v(x,y) ‖ M4| ≨ |c(z) - M| , y us`ahb om tobron` ho
⇙) Fbnb om nöhumb ho ua fbnpmoeb os noabr b gku`m quo m` sun` hom v`mbr `dsbmutb ho m`
p`rto ro`m y om v`mbr `dsbmutb ho m` p`rto gn`kga`rg`, pbhonbs fbasghor`r quo 5 9 ≨ |c(z) ‖ M| ≨ |u(x,y) ‖ M0| + |v(x,y) ‖ M4 | , y us`ahb om tobron` ho gatorf`m gatorf`m`fgöa `fgöa so bdtgoao mb dusf`hb.
⊟ Bdsorv`fgöa Xoagoahb oa fuoat` mb `cgrn`hb oa m` `ftgvgh`h 8, pbhonbs hofgr quo om fàmfumb ho ua mîngto oa v`rg`dmo fbnpmoe` puoho rohufgrso `m fàmfumb ho mbs mîngtos hbdmos ho sus fbnpbaoatos ro`m o gn`kga`rg`. Oeonpmbs
0-
mîn z ↔g
0 z-g z-g mîn mîn > > z 4 + 0 z ↔g (z + g )( z ∔ g ) z ↔g z + g
>
0 4g
>∔
g 4
z4 > 2 , oa osto f`sb puoho dusf`rso m` p`rto ro`m o gn`kga`rg` ho m` cuafgöa y muokb 4- mîn z ↔9 | z | f`mfum`r mbs mîngtos hbdmos ho f`h` ua` ho omm`s p`r` (x,y) ↔ (9,9). Fbnb ostb os d`st`ato m`rkb pbhonbs `a`mgz`r om nöhumb ho m` m ` cuafgöa y bdsorv`r quo5 6
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0
z 4 | z |4 9≨ > >| z | , sg tbn`nbs k(z) > 9 , l(z) > |z| y mm`n`nbs c(z) ` m` cuafgöa h`h` |z| |z| vonbs quo |k(z)| ≨ |c(z)| ≨ |l(z)| y fbnb mîn k(z) > mîn l(z) > 9 oatbafos us`ahb om z↔9
tobron` ho gatorf`m`fgöa bdtoaonbs `cgrn`r quo
mîn c(z) z ↔9
>
z↔9
9 y us`ahb `) ho m` `ftgvgh`h 4 pbhonbs
mîn c(z) > 9 z ↔9
@ftgvgh`h ?5
∃
F`mfum`r mbs sgkugoatos mîngtos
To(z 4 ) d) mîn z ↔9 z
z -0 `) mîn z ↔0 z ∔ 0
Gn(z 4 ) f) mîn z ↔9 z
6- Fbatgaugh`h oa ua puatb y oa ua hbngagb ♣ _a` cuafgöa c(z) os fbatgau` oa z9 sî y sömb sî ♣ _a` cuafgöa
mîn c(z) > c(z 9 )
z ↔z 9
c(z) os fbatgau` oa ua hbngagb H sg os fbatgau` oa f`h` puatb ho H.
@ftgvgh`h 35
∃
H`h` c(z) > u(x,y) + g v(x,y) y
z9 > x9 + g y9 , eustgcgf`r quo5
c(z) os fbatgau` oa z9 ⇘ u(x,y) y v(x,y) sba fbatgau`s oa (x9 , y9) _s`r om rosumt`hb ho m` `ftgvgh`h 8 y m` hocgagfgöa ho fbatgaugh`h.
⊟ Bdsorv`fgbaos
y oeonpmbs5
H`hb quo m` hocgagfgöa ho fbatgaugh`h os ghçatgf` ` m` hocgagfgöa ho fbatgaugh`h ho ua` cuafgöa ho ua` v`rg`dmo ro`m, pbhonbs oauafg`r m`s sgkugoatos prbpbsgfgbaos, fuy`s honbstr`fgbaoss sba ox`ft`noato m`s ngsn`s quo m`s utgmgz`h`s oa om f`sb ro`m. honbstr`fgbao 0- M` sun` , rost` y prbhuftb ho cuafgbaos fbatgau`s os fbatgau`. Om fbfgoato ho cuafgbaos fbatgau`s os fbatgau` s`mvb oa mbs puatbs oa quo so `aum` om hoabnga`hbr. 4- M` fbnpbsgfgöa ho cuafgbaos fbatgau`s os ua` cuafgöa fbatgau`. 4 a 6- Mbs pbmgabngbs fbnpmoebs c(z) > `9 + `0 z + `4 z +……+ `a z sba ffbatgaubs batgaubs p`r` p`r` tbhb tbhb z
@ftgvgh`h ;5
∃
0- Eustgcgf`r pbrquç m`s sgkugoatos prbpbsgfgbaos sba vorh`hor`s5 `)
k0(z) > To(z) os fbatgau` oa F 8
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 d) f) h) o)
k4(z) > |z | os fbatgau` oa F k6(z) > Gn(z6-6) os fbatgau` oa F k8(z) >@rk(z) ab os fbatgau` oa om fbaeuatb {(x,9) / x ≨ 9} k?(z) > @rk(z-4) ab os fbatgau` oa om fbaeuatb fbaeuatb {(x,9) / x ≨ 4}
8- Horgv`h` Lonbs vgstb quo mbs mîngtos y m` fbatgaugh`h ho m`s cuafgbaos fbnpmoe`s so rohufoa ` mbs mîngtos y m` fbatgaugh`h ho p`ros ho cuafgbaos ro`mos ho hbs v`rg`dmos ro`mos. Ybhrî` froorso quo m` horgv`dgmgh`h ho ua` cuafgöa c(z) os rohufgdmo ` m` ho sus p`rtos ro`m o gn`kga`r`, porb voronbs quo ostb ab os `sî y sba os`s hgcoroafg`s m`s quo h`a gatorçs ` m` tobrî`. ♣ Vg
c(z) ostà hocgagh` oa ua oatbrab ho z9 , oatbafos m` horgv`h` ho c(z) oa z9 , ` m` quo c(z + ∃z) - c(z 9 ) fu`ahb osto mîngto oxgsto. gahgf`nbs c '(z9) , ostà h`h` pbr c ' ( z 9 ) > mîn 9 ∃z ↔ 9 ∃z
⊟ Bdsorv`fgbaos5 H`hb quo m` hocgagfgöa ho horgv`h` tgoao m` m ` ngsn` cbrn` quo m` hocgagfgöa ho horgv`h` ho ua` cuafgöa ho ua` v`rg`dmo ro`m, pbhonbs oauafg`r m`s sgkugoatos prbpbsgfgbaos, fuy`s honbstr`fgbaoss sba ox`ft`noato m`s ngsn`s quo m`s utgmgz`h`s oa om f`sb ro`m. honbstr`fgbao 0- M` cuafgöa fbast`ato
c(z) > j os horgv`dmo p`r` tbhb z y c '(z) > 9. a
4- Vg a os ua aõnorb a`tur`m, c(z) > z os horgv`dmo p`r` tbhb z y , sg a os ua aõnorb oatorb a a‖0 aok`tgvb, c(z) > z os horgv`dmo p`r` tbhb z ≩ 9 . Oa `ndbs f`sbs so funpmo c '(z) > az . 6- Vg c(z) os horgv`dmo oa z9 oatbafos c(z) os fbatgau` oa z9 .
c(z) y k(z) sba horgv`dmos oa ua hbngagb H oatbafos c(z) ° k(z) , c(z). k(z) , c(z) /k(z) , fba k(z) ab aum` oa H y c(k(z)) sba horgv`dmos oa H y so funpmo5
8- Vg
`)
Zc(z) ° k(z)^'> c '(z) ° k'(z)
d)
Zc(z) . k(z)^' > c '(z) k(z) + c(z) k'(z)
f)
Zc(z) / k(z)^'> Zc '(z) k(z) ‖ c(z) k'(z)^ / Zk(z)^ 4
h) h) Zc(k(z))^'> c '(k(z)) k'(z) Oeonpmbs
0- Mbs pbmgabngbs fbnpmoebs
c(z) > `9 + `0 z + `4 z4 +……+ `a za sba hhorgv`dmos orgv`dmos p`r` tbhb z
?
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 4- M`s cuafgbaos r`fgba`mos, os hofgr `quomm`s quo sba fbfgoato ho pbmgabngbs oa horgv`dmos oa tbhbs mbs fbnpmoebs quo ab `aumoa om hoabnga`hbr.
z, sba
4
6- Vg quoronbs s`dor sg c(z) > |z| os horgv`dmo , f`mfum`nbs
| z + ∃z | 4 - | z | 4 c(z + ∃z) - c(z ) > mîn mîn (0), fbnb osto mîngto os gahotornga`hb `a`mgz`nbs ∃z ↔ 9 ∃z ↔ 9 ∃z ∃z mbs sgkugoatos hbs f`sbs 5 - Vg ∃z os ro`m, os hofgr sg ∃z > ∃x + 9 g , oatbafos
| z + ∃x | 4 - | z | 4 (0) > mîn ∃x ↔ 9 ∃x
4x∃x + ∃x 4 (x + ∃x)4 + y 4 - ( x 4 + y 4 ) > mîn > mîn ∃x ↔ 9 ∃x ↔ 9 ∃x ∃x
>
4x
- Vg ∃z os gn`kga`rgb purb, os hofgr sg ∃z > 9 + g ∃y , oatbafos
| z + g∃y | 4 - | z | 4 (0) > mîn ∃y ↔9 g∃ y
x 4 + (y + ∃y) 4 - ( x 4 > mîn ∃ y ↔9 g∃ y
+y
4
)
4y∃y + ∃y 4 > mîn ∃y ↔ 9 g ∃y
>
4y g
> ∔ g 4y
4
Vg 4x ≩ - g 4y oatbafos om om mîngto (0) ab oxgsto y pbr pbr mb t`atb c(z) > | z | ab os horgv`dmo. Fbnb m` gku`mh`h 4x > - g 4y sömb os vorh`hor` sg x > 9 o y > 9 , pbhonbs `cgrn`r quo sg z ≩ 9 oatbafos c(z) > | z |4 ab os horgv`dmo.
4yy , os hofgr sg x > y > 9 b z > 9 , oatbafos mbs hbs mîngtos `atorgbros sba gku`mos, Vg 4x > - g 4 porb ostb ab `mf`az` p`r` `cgrn`r quo om mîngto (0) oxgsto. Y`r` `vorgku`r sg os horgv`dmo oa z > 9 f`mfum`nbs om mîngto (0) oa hgflb puatb5 | ∃z | 4 - | 9 | 4 c(9 + ∃z) - c(9) mîn > mîn ∃z ↔ 9 ∃z ↔ 9 ∃z ∃z
| ∃z | 4 > mîn ∃z ↔ 9 ∃z
>
mîn
∃z ↔ 9
∃z ∃z ∃z
>
mîn ∃z > 9
∃z ↔ 9
4
Muokb pbhonbs `cgrn`r quo
c(z) > | z | sömb os horgv`dmo oa z > 9 y so vorgcgf` c '(9) > 9
4
Fbnb c(z) > | z | os fbatgau` p`r` tbhb z, osto oeonpmb abs nuostr` quo ua` cuafgöa puoho sor fbatgau` y ab sor horgv`dmo. 4
4
4
Osto oeonpmb t`ndgça abs nuostr` quo sg z > x + gy oatbafos m` cuafgöa cuafgöa c(z) > | z | > x + y , os ua pbmgabngb oa m`s v`rg`dmos x , y , p`rofo gabcoasgv` y sga ond`rkb sömb sömb tgoao horgv`h` oa
z>9 Abs prokuat`nbs5 ² os pbsgdmo `vorgku`r sg ua` cuafgöa tgoao b ab horgv`h` sga us`r m`
hocgagfgöa2 Mbs tobron`s quo so hos`rrbmm`a ` fbatgau`fgöa abs h`ràa m` rospuost` ` osto gatorrbk`ato. g atorrbk`ato. 3
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 Α Fbahgfgöa
aofos`rg` ho oxgstoafg` ho horgv`h`
c(z) > u(x,y) + g v(x,y) os horgv`dmo oa z9 >x 9 + g y 9 oatbafos u(x,y) y v(x,y) vorgcgf`a oa ∄u(x 9 , y 9 ) ∄v(x 9 , y 9 ) > ∄x ∄y (F.T) (x9, y9) m`s fbahgfgbaos ho F`ufly Tgon`aa 5 ∄u (x 9 , y 9 ) ∄v (x 9 , y 9 ) Vg
c '(z9) >
@honàs so vorgcgf` quo
∄ u(x 9 , y 9 ) ∄x
∄ v(x ,yy ) ∄ 9 9
+ g
∄x
>∔
∄
x
>
∄v (x 9 , y 9 ) ∄y
∔ g
∄u(x 9 , y 9 ) ∄y
Honbstr`fgöa Ybr sor c(z) horgv`dmo oa z9 , s`donbs quo c ' ( z 9 ) >
c(z 9 + ∃z) - c(z 9 ) y osto mîngto oxgsto ∃z ↔ 9 ∃z mîn
gahopoahgoatonoato gahopoahgoato noato hom nbhb oa quo ∃z tgoah` ` forb. Fbasghor`ahb ∃z > ∃x + g 9 , os hofgr tbn`ahb ∃y > 9, om mîngto `atorgbr tbn` m` cbrn`5
c ' ( z 9 ) > mîn
u(x 9 + ∃x, y 9 ) + g v(x 9 + ∃x, y 9 ) - u(x 9 , y 9 ) ∔ g v(x 9 , y 9 ) ∃
∃x ↔ 9
x y `krup`ahb m`s p`rtos ro`mos o gn`kga`rg`s y toagoahb oa fuoat` quo om mîngto oxgsto so bdtgoao
c ' ( z 9 ) >
∄u(x 9 , y 9 ) ∄x
+ g
∄v (x 9 , y 9 ) ∄x
(*)
Fbasghor`ahb ∃z > 9 + g ∃y , os hofgr tbn`ahb ∃x > 9, om mîngto tbn` m` cbrn`5
u(x 9 , y 9 + ∃y) + g v(x 9 , y 9 + ∃y) - u(x 9 , y 9 ) ∔ g v( x 9 , y 9 ) ∃ y ↔9 g∃ y ∄v (x 9 , y 9 ) ∄u(x 9 , y 9 ) (**) y bpor`ahb fbavoagoatonoato so bdtgoao c ' ( z 9 ) > ∔ g ∄y ∄y c ' ( z 9 ) > mîn
Fbnp`r`ahb (*) y (**) , toaonbs m` gku`mh`h oatro hbs fbnpmoebs, pbr mb t`atb sus p`rtos ro`mos sba gku`mos oatro sî y t`ndgça sus p`rtos gn`kga`rg`s y m`s gku`mh`hos bdtoagh`s sba eust`noato m`s fbahgfgbaos fbahgfgbaos ho FT, quo quorî`nbs honbstr`r. honbstr`r.
⊟ Bdsorv`fgöa5 Vg u(x,y) y v(x,y) ab s`tgsc`foa m`s fbahgfgbaos ho (F.T) oa (x9, horgv`dmo oa z9 >x9 + g y9 (Fbatr` rofîprbfb hom tobron` `atorgbr)
y9) oatbafos c(z) ab os
Oeonpmb 4
Vg quoronbs s`dor hbaho os horgv`dmo m` cuafgöa c(z) > x y - gxy oatbafos dusf`nbs su p`rto ro`m o gn`kga`rg` , oa osto f`sb u(x,y) > xy , v(x,y v(x,y)) > -x -xyy4 y pm`ato`nbs m`s fbahgfgbaos ho FT 5 ;
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0
ux > vy ⇔ y > -4xy ⇔ y (0 + 4x) > 9 uy > -vx ⇔ x > y4 Fbnb m` prgnor` ofu`fgöa os om prbhuftb ho hbs c`ftbros gku`m`hb ` forb, `mkuab ho ommbs hodorà sor forb , pbr mb t`atb y > 9 ö x > -0/4. Toonpm`z`ahb oa m` sokuah` ofu`fgöa vonbs quo 5 sg y > 9 oatbafos x > 9, 4
sg x > -0/4 , oatbafos so bdtgoao
y > -0/4 , quo ab tgoao sbmufgöa puos y os ro`m Ybr mb t`atb m`s fbahgfgbaos ho FT sömb so vorgcgf`a oa z > 9 + g 9 > 9 , pbhonbs `cgrn`r oatbafos quo m` cuafgöa h`h` ab os horgv`dmo sg z ≩9 , porb ab pbhonbs `cgrn`r sg os b ab horgv`dmo oa hgflb puatb puos om tobron` `atorgbr sömb gahgf` ua` fbahgfgöa aofos`rg` ho horgv`dgmgh`h porb ab ua` fbahgfgöa sucgfgoato.
Α Fbahgfgöa
sucgfgoato ho oxgstoafg` ho horgv`h`
Vg u(x,y) y v(x,y) tgoaoa horgv`h`s p`rfg`mos fbatgau`s oa (x9, y9) y vorgcgf`a puatb oatbafos c(z) > u(x,y) + g v(x,y) os horgv`dmo oa z9 >x9 + g y9
(F.T) oa hgflb
Honbstr`fgöa Fbasghor`ahb quo ∃z > ∃x + g ∃y , toaonbs quo honbstr`r quo oxgsto om sgkugoato mîngto
u(x 9 + ∃x, y 9 + ∃y) + g v(x 9 + ∃x, y 9 + ∃y) - u(x 9 , y 9 ) ∔ g v( x 9 , y 9 ) > (#) ( ∃x , ∃y ) ↔ ( 9 , 9 ) ∃ x + g ∃y mîn
Fbnb m`s horgv`h`s p`rfg`mos ho u(x,y) y v(x,y) sba fbatgau`s oa (x9, y9), oatbafos hgfl`s cuafgbaos sba hgcoroafg`dmos oa (x9, y9) y pbr mb t`atb puohoa `prbxgn`rso oa ua oatbrab ho hgflb puatb pbr om pm`ab t`akoato, `sî pbhonbs osfrgdgr 5
u(x,y) > u(x9, y9) + u'x (x9, y9) (x - x9) + u'y (x9, y9) (y - y9) + O0(x ‖ x9, y ‖ y9) v(x,y) > v(x9, y9) + v'x (x9, y9) (x - x9) + v'y (x9, y9) (y - y9) + O4(x ‖ x9, y ‖ y9) hbaho O0 y O4 tgoahoa ` forb nàs ràpghb quo m` hgst`afg` quo sop`r` mbs puatbs (x,y) y (x9, y9) Vg fbasghor`nbs x ‖ x9 > ∃x , y ‖ y9 > ∃y oxprosgbaos `atorgbros puohoa osfrgdgrso fbnb5
y us`nbs m` m`ss fbahgfgbaos fbahgfgbaos ho (FT) , m`s
u(x9 + ∃x, y9 + ∃y) - u(x9, y9) > u'x (x9, y9) ∃x - v'x (x9, y9) ∃y + O0(∃x, ∃y)
(0)
v(x9 + ∃x, y9 + ∃y) - v(x9, y9) > v'x (x9, y9) ∃x + u'x (x9, y9) ∃y + O4(∃x, ∃y)
(4)
hbaho
mîn
( ∃ x , ∃ y ) ↔( 9 , 9 )
O e ( ∃x, ∃y ) 4
∃ x + ∃y
4
>
9 , p`r` e > 0,4
<
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 puos ∃x 4 + ∃y 4 os m` hgst`afg` oatro mbs puatbs (x9 + ∃x ,y9 + ∃y) y
(x9, y9) y tgoaho ` 9
sî y sömb sî sî (∃x, ∃y) tgoaho ` (9,9) Toonpm`z`ahb (0) y (4) oa (#) y `krup`ahb `krup`ahb fbavoagoatonoato fbavoagoatonoato toaonbs5
(#) >
O ( ∃x, ∃y ) + gO 0 ( ∃x, ∃y ) u' x (x 9 , y 9 ) + g v'x (x 9 , y 9 ) + 0 > ∃ ∃ ↔ ( x , y ) ( 9,9 ) ∃x + g∃y
mîn
> u‗x (x9, y9) + g v‗x (x9, y9)
puos om mîngto hom õmtgnb fbfgoato v`mo forb puos pbhonbs pbhonbs `fbt`rmb ho m` sgkugoato n`a n`aor` or`
9≨
O 0 ( ∃x, ∃y ) + gO 0 ( ∃x, ∃y ) ∃x + g∃ y
≨
| O 0 ( ∃ x , ∃y ) | | O 4 ( ∃ x , ∃y ) | y us`ahb om tobron` ho + 4 4 4 4 ∃ x + ∃y ∃x + ∃y
gatorf`m`fgöa fbafmugnbs quo om mîngto (#) oxgsto y pbr mb t`atb
c(z) os horgv`dmo oa z9
@atos ho h`r `mkuabs oeonpmbs hocgagnbs om fbafoptb nàs gnpbrt`ato ho m`s cuafgbaos ho v`rg`dmo fbnpmoe`5 m` `a`mgtgfgh`h.
?- @a`mgtgfgh`h @a`mgtgfgh`h ♣ Vg
c(z) os horgv`dmo oa z9 y oa tbhb ua oatbrab ho z9, so hgfo quo c(z) os `a`mîtgf` oa z9
⊟ Bdsorv`fgbaos5 0- Vg u(x,y) y v(x,y) tgoaoa horgv`h`s p`rfg`mos fbatgau`s oa ua oatbrab ho z9 y funpmoa (F.T) oa hgflb oatbrab oatbafos c(z) os `a`mîtgf` oa z9. 4- Vg u(x,y) y v(x,y) tgoaoa horgv`h`s p`rfg`mos fbatgau`s oa ua hbngagb `dgortb H y funpmoa (F.T) oa H oatbafos c(z) os `a`mîtgf` oa H. Oeonpmbs
Vg quoronbs l`mm`r om hbngagb ho fbatgaugh`h, horgv`dgmgh`h y `a`mgtgfgh`h ho m`s sgkugoatos cuafgbaos, prbfohonbs prbfohonbs ho m` n`aor` quo so gahgf` ` fbatgau`fgöa5
0- c(z) > 6 z8 ‖ 4gz + 8 ‖ g Oa osto f`sb soafgmm`noato hofgnbs quo c os fbatgau`, horgv`dmo y `a`mîtgf` p`r` tbhb z, pbr sor sun` y prbhuftb ho cuafgbaos fbatgau`s, horgv`dmos y `a`mîtgf`s oa tbhb F.
4- c(z) > x4 y + g (y4 ‖ x) ⇔ u(x,y) > x4 y , v(x,y) > y4 ‖ x Fbnb u(x,y) y v(x,y) sba fbatgau`s p`r` tbhb p`r ho aõnorbs ro`mos (x,y) ⇔ om hbngagb ho fbatgaugh`h ho c os om fbaeuatb F. 7
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 Y`r` `vorgku`r höaho os horgv`dmo, pm`atonbs m`s fbahgfgbaos ho (F.T)5
u x u y
v y ⇔ 4xy > 4y 4 > ∔vx ⇔ x > 0
>
y rosbmvonbs om sgston` ho ofu`fgbaos bdtoaghb5 bdtoaghb5 4xy > 4y ⇔ 4y (x ‖ 0) > 9 ⇔ y > 9 b x > 0 4 > 0 xfbndga`ahb ⇔ x > 0 b x > - 0 mbs rosumt`hbs bdtoaghbs, pbhonbs `cgrn`r quo5 sg x > 0 so s`tgsc`foa `nd`s ofu`fgbaos (sga gnpbrt`r om v`mbr ho y) , t`ndgça so s`tgsc`foa sg (x,y) > (-0,9) , pbr mb t`atb5
- Vg x ≩ 0 b (x,y) ≩ (-0,9) , m`s fbahgfgbaos ho (F.T) ab so vorgcgf`a y pbr mb t`atb c ab os horgv`dmo oa hgflbs puatbs( tobron` ho fbahgfgöa aofos`rg`) - Om fbaeuatb cbrn`hb pbr m` roft` x > 0 y om puatb (-0,9) os om hbngagb ho horgv`dgmgh`h ho c puos puos oa ommbs, `honàs ho funpmgrso m`s fbahgfgbaos ho (F.T) m`s cuafgbaos u(x,y) y v(x,y) tgoaoa horgv`h`s p`rfg`mos fbatgau`s (tobron` ho fbahgfgöa sucgfgoato)
c '(0+ gy) >
∄ u(0, y )
c '(-0 + 9g) > 6- c(z)
-0
0
c os v`fîb puos os gnpbsgdmo oafbatr`r oatbrabs ho
Om hbngagb ho `a`mgtgfgh`h ho horgv`dgmgh`h. @honàs su horgv`h` v`mo5
y
∄x ∄u(∔ 0,9 ) ∄x
∄v (0, y )
> 4y + g ∄x ∄v (∔ 0,9 ) > g + g ∄x
+ g
,
> (y4 ‖ x) + g x4 y ⇔ u(x,y) > y4 ‖ x , v(x,y) > x4 y
Om hbngagb ho fbatgaugh`h os tbhb sor pbmgabngbs.
F, puos u(x,y) y v(x,y) sba fbatgau`s p`r` tbhb (x,y) pbr
Vg pm`atonbs m`s fbahgfgbaos ho (F.T) bdtoaonbs 5
u x u y
v y ⇔ ∔0 > x 4 > ∔ v x ⇔ 4 y > ∔4xy
>
y ràpgh`noato pbhonbs `cgrn`r quo osto sgston` ab tgoao sbmufgöa puos m` ofu`fgöa ab so s`tgsc`fo p`r` agakõa aõnorb ro`m x. Ybr mb t`atb om hbngagb ho horgv`dgmgh`h os v`fîb y om ho `a`mgtgfgh`h t`ndgça os v`fîb.
x4 > -0
8- c(z) > ox fbs y + g o x soa y ⇔ u(x,y) > ox fbs y , v(x,y) > ox soa y Om hbngagb ho fbatgaugh`h ho c os om fbaeuatb F puos t`atb u(x,y) fbnb v(x,y) sba fbatgau`s p`r` tbhb p`r ho aõnorbs ro`mos (x,y) Ym`ato`ahb m`s fbahgfgbaos ho (F.T) bdtoaonbs om sgston`5
09
Nöhumb G - _agh`h 0
x
N`tonàtgf` H y H0
u x u y
v y ⇔ o x fbs y > o x fbs y x x > ∔ v x ⇔ ∔o soay > ∔o soay
>
quo mb s`tgsc`foa tbhbs mbs p`ros (x,y) ho aõnorbs ro`mos, fbnb `honàs u y v tgoaoa horgv`h`s p`rfg`mos fbatgau`s pbhonbs `cgrn`r quo c os horgv`dmo y `a`mîtgf` oa tbhb F. x x + g vx > @honàs su horgv`h` os c 'c (z) ost` cuafgöa vorgcgf` quo '(z)>>uc(z)
x
o fbs y + g o soa y . Os gatoros`ato bdsorv`r quo
z4 ?- c ( z ) > 0 + z4 Oa osto f`sb rofbabfonbs quo t`atb om aunor`hbr fbnb om hoabnga`hbr sba fbatgaubs, horgv`dmos y `a`mîtgfbs oa tbhb F pbr sor pbmgabngbs oa v`rg`dmo z , pbr mb t`atb c os fbatgau`, horgv`dmo y `a`mîtgf` oa tbhb F s`mvb oa mbs puatbs ° g , hbaho so `aum` om hoabnga`hbr y quo `honàs ab portoaofoa ` su hbngagb.
| z |4 3- c ( z ) > 0 + z4 Mbs puatbs ° g `aum`a om hoabnga`hbr hoabnga`hbr y pbr mb t`atb ab portoaofoa portoaofoa `m hbngagb, cuor` ho ommbs c os fbatgau` pbr sor fbfgoato ho fbatgau`s, pbr mb t`atb om hbngagb ho fbatgaugh`h ho c os os F ‖
{ g , -g}. 4
4
Fbnb s`donbs quo 0 + z os horgv`dmo p`r` tbhb z y | z | sömb oa horgv`dmo oa z9 > 9, pbhonbs `cgrn`r quo c os horgv`dmo oa z9 > 9 pbr sor fbfgoato ho horgv`dmos y om hoabnga`hbr ab so `aum`. @a`mgfonbs sg c puoho puoho sor horgv`dmo oa `mkõa btrb puatb hom hbngagb, p`r` ommb supbak`nbs quo oxgsto ua fbnpmoeb z0 , fba z0 ≩ 9 y z0 ≩ ° g , t`m quo c so` horgv`dmo oa z0 , oatbafos r`zba`ahb hom sgkugoato nbhb5 c ( z ) . (0 + z 4 ) > | z |4 {
horgv`dmo oa z0
0 8 4 8 6
horgv`dmo oa z 0
{
ab os horgv`dmo oa z 0
088 8 488 8 6
oshorgv`dmo oa z0 ,pbr sor prbhuftb hohorgv`dmos
bdtoaonbs ua` fbatr`hgffgöa, pbr mb t`atb ab puoho oxgstgr oso fbnpmoeb z0 . Fbafmugnbs oatbafos quo c sömb os horgv`dmo oa z9 > 9 y pbr mb t`atb om hbngagb ho `a`mgtgfgh`h os v`fîb.
• Oeorfgfgbs 0- F`mfum`r us`ahb m` hocgagfgöa, m` horgv`h` ho5 `) l0(z) > Gn(z)
d) l4(z) > z . To(z)
4
f) l6(z) > |z |
h) l8(z (z)) >
z
4- Gahgf`r om hbngagb y horgv`r m`s sgkugoatos cuafgbaos us`ahb rokm`s5 00
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0
`) j0(z) > 6 z
4
4
‖ 0/z
d) j0(z) > z
8 6
. (-g + z )
6- Vg c(z) os horgv`dmo, horgv`dmo, f`mfum`r m` horgv`h` ho `)
( 4z ∔ 0) 8 f) j6(z) > 0 ∔ ( 4z ) 4
w > z . Zc(z)^4 d) w > c(z6) ‖ 4 c(6z)
8- H`h`s m`s cuafgbaos c(z) > z , k(z) > To(z) , l(z) > Gn(z), fbnprbd`r quo5 `) c(z) ab os horgv`dmo oa agakõa puatb porb C(z) > z c(z) os horgv`dmo oa om brgkoa. K(z) (z) > c(z) (k (k(z)) (z))4 os horgv`dmo oa (9,y), ∉ y.. d)k(z) ab os horgv`dmo oa agakõa puatb porb K d) l(z) ab os horgv`dmo oa agakõa puatb y L(z) > c(z) ‖ k(z) + gl(z) os horgv`dmo ∉ z. f) V`f`r fbafmusgbaos. ?- Vg c(z) os fbatgau` oa z9 y k(z) > z y vorgcgf` l‗(z9) > 4z9 c(z9)
4
- z94 , honbstr`r quo l(z) > c(z) . k(z) os horgv`dmo oa z9
3- L`mm`r y kr`cgf`r om hbngagb ho horgv`dgmgh`h y ho `a`mgtgfgh`h ho m`s sgkugoatos cuafgbaos y f`mfum`r c ‗(z) oa mbs puatbs hbaho oxgst` 4
6
6
`) C0(z) > 6xy + g (y ‖ x f) C6(z) > z (soax - g y)
)
d) C4(z) h) C8(z)
> -4y x4 + 3x4+ g (4x4 +3 yx4 ) > o4x (8 x y4 + y4 g)
;- Honbstr`r5 `) Vg c(z) y |c(z)| sba `nd`s `a`mîtgf`s oa H ⇔ c(z) os ua` cuafgöa fbast`ato oa H. d) Vg k(z) y k( z ) sba `nd`s `a`mîtgf`s ⇔ k(z) os fbast`ato 4 f) Vg l(z) > u(x,y)+ g Zu(x,y)^ os `a`mîtgf` ⇔ l(z) os fbast`ato x x6 + y 6 +g 4 sg (x,y) ≩(9,9) y c(9,9) > 9 : nbstr`r quo s`tgsc`fo x + y4 m`s fbahgfgbaos ho F`ufly Tgon`aa oa (9,9) porb ab os horgv`dmo oa z > 9
x6 ∔ y 6 7- H`h` c(z) > 4 x + y4
09- Vg c(z) > u(x,y) + g v(x,y) y oxpros`nbs x o y oa fbbrhoa`h`s pbm`ros toaonbs quo c(z) > u(r fbs μ , r soaμ) + g v(r fb fbss μ , r soaμ) > _(r, μ) + g S(r, μ) , honbstr`r quo sg c gμ os horgv`dmo oa z > r o , oatbafos so vorgcgf`a m`s sgkugoatos fbahgfgbaos ho (F.T)5 ∄_ 0 ∄S ∔ gμ ∄r > r ∄μ ∄S ∄_ ∄_ ∄S o ∔ g μ , (F.T oa pbm`ros) y c ' ( z ) > o ∔g +g , r ≩ 9 > ∄S ∄_ 0 r r r ∄ μ ∄ μ ∄ ∄ >∔ r ∄μ ∄r 00- Vg c(z) os `a`mîtgf` oa ua fbaeuatb `dgortb H y z9 portoaofo ` H eustgcgf`r quo m` cuafgöa c ( z ) ∔ c ( z 9 ) sg z ∌ H - {z 9 } k( z ) > z ∔ z 9 os `a`mîtgf` `a`mîtg f` oa H ‖ {z9} y os fbatgau` oa z9 c ' ( z 9 ) sg z > z 9
04
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0
3- Cuafgbaos omonoat`mos x
Oa v`rg`dmo ro`m so tgoaoa m`s cuafgbaos o . soa x , fbs x , ma x , ²pbhràa oxtoahorso hgfl`s cuafgbaos ` m` v`rg`dmo fbnpmoe`2 @ fbatgau`fgöa oafbatr`ronbs oafbatr`ronbs m` rospuost`. r ospuost`.
♣
Cuafgöa Oxpbaoafg`m Oxpbaoafg`m
Vo protoaho hocgagr m` m ` oxpbaoafg`m fbnpmoe` c(z) > oz ho nbhb quo sg z os ro`m fbgafgh` fba x m` oxpbaoafg`m ro`m, os hofgr hodonbs oxgkgrmo quo c(x + g 9) > o . x x Fbnb m` horgv`h` ho o os gku`m ` o , os a`tur`m gnpbaor quo c '(z) > c(z) p`r` tbhb z. x
Lonbs vgstb oa om oeonpmb 8 ho m` soffgöa `atorgbr quo m` cuafgöa c(z) > o (fbs y + g soa y) x vorgcgf` quo c '(z) > c(z) p`r` tbhb z y `honàs funpmo quo c(x + 9g) > o , pbr ommb m` oxpbaoafg`m fbnpmoe` so hocgao fbnb so gahgf` ` fbatgau`fgöa y rosumt` sor `a`mîtgf` oa tbhb om pm`ab fbnpmoeb.
♣
Cuafgöa oxpbaoafg`m oxpbaoafg`m5 oxp(z) > oz > ox (fbs y + g soa y)
∃
@ftgvgh`h o z f) o ≩ 9 ,∉z gy h) | o | > 0 , p`r` y ro`m z o) o > 0 ⇘ z > g 4j ω , fba j oatorb
)‗> oz
o z0 > o z 4 ⇘ z0 ‖ z4 > g 4jω , fba j oatorb z +z z z k) o 0 4 > o 0 . o 4
c)
♣
Cuafgöa Mbk`rgtnb Mbk`rgtnb
Oa v`rg`dmo ro`m, m` cuafgöa mbk`rgtnb os m` gavors` ho m` cuafgöa oxpbaoafg`m y sg
y > ma x Yrotoahonbs hocgagr
y
⇘ o
x 1 9, v`mo 5
> x
w > ma z , ho nbhb quo ow > z , ²sorà pbsgdmo2
Fbnb m` oxpbaoafg`m fbnpmoe` auaf` so `aum` ho oatr`h` pohgnbs quo fbasghor`nbs w > u + g v , oatbafos5
z
≩
9 y sg
ow > z ⇔ ou (fbs v + g soa v) > z ⇔ ou > | z | , v > `rk(z) > μ + 4jω , fba j > 9, °0, °4,…. Ho m` oxprosgöa ro`m
ou > | z | pbhonbs bdtoaor quo u > ma | z | , pbr mb t`atb 5
w > ma z > u + g v > ma | z | + g (μ + 4jω) , fba j > 9, °0, °4,…. 06
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 quo ovghoatonoato ab os cuafgöa puos p`r` fbnpmoeb mbk`rgtnb
z ≩ 9 bdtoaonbs gacgagtbs v`mbros hom
Ost` bdsorv`fgöa gagfg`m porngto h`r m` sgkugoato hocgagfgöa5
♣
Mbk`rgtnb fbnpmoeb 5 ma z > ma | z | + g ( μ + 4jω) p`r` z ≩ 9
Vg cge`nbs om v`mbr ho j oa m` hocgagfgöa `atorgbr y ospofgcgf`nbs om v`mbr hom `rkunoatb μ tr`ascbrn`nbs `m mbk`rgtnb oa ua` cuafgöa, pbr oeonpmb5 Vg
j > 9, pbhonbs hocgagr m`s sgkugoatos cuafgbaos 5
c 0(z) > ma | z | + g μ ,fba -ω = μ ≨ ω c 4(z) > ma | z | + g μ ,fba 9 ≨ μ = 4 ω c 6(z) > ma | z | + g μ ,fba ω ≨ μ = 6 ω Vg j > 0, pbhonbs hocgagr m`s sgkugoatos cuafgbaos 5
c 8(z) > ma | z | + g (μ +4ω) fba -ω = μ ≨ ω c ?(z) > ma | z | + g (μ +4ω) fba μ9 ≨ μ = μ9 + 4 ω Ho m`s gacgagt`s cuafgbaos quo puohoa hocgagrso ` p`rtgr hom mbk`rgtnb fbnpmoeb, so hgstgakuo ua`, quo so hoabnga` r`n` prgafgp`m hom mbk`rgtnb, so gahgf` Ma z y so hocgao fbnb5
♣
T`n` prgafgp`m ho m` cuafgöa mbk`rgtnb mbk`rgtnb5 Ma z > ma | z | + g @rk(z), fba z ≩ 9 y -ω = @rk(z) ≨ ω
Bdsorv`r quo5 `) Om hbngagb ho Ma z os F ‖ {9} d) Fbnb ma | z | os fbatgau` p`r` z ≩ 9 y @rk(z) os fbatgau` s`mvb oa om oeo ro`m aok`tgvb, om hbngagb ho fbatgaugh`h ho Ma z os F ‖ {z > x + g9 , x ≨ 9} f) Fbnb Ma z ab os fbatgau` oa om oeo ro`m aok`tgvb, ab puoho toaor horgv`h` sbdro hgflb songoeo, porb puoho vorso càfgmnoato us`ahb (F.T) oa pbm`ros y `a`mgz`ahb m` fbatgaugh`h ho m`s horgv`h`s p`rfg`mos ho m` p`rto ro`m o gn`kga`rg` quo om hbngagb ho horgv`dgmgh`h y `a`mgtgfgh`h os F ‖ {z > x + g9 , x ≨ 9} y so funpmo ( Ma z)'> 0/ z Oeonpmbs
0- 4-
ma g > ma | g | + g `rk (g) > ma 0 + g ( ¾ ω + 4jω) > g (¾ ω + 4jω), j > 9, ° 0, ° 4,…. Ma g > ma | g | + g @rk (g) > g ¾ ω
ma (-0 + g) > ma |-0 + g | + g `rk(-0 `rk(-0 + g) > ma 4 + g ( ± . ω + 4jω), j > 9, ° 0, ° 4,…. g) > ma |-0 + g | + g @rk(-0 + g) > ma 4 + g ± ω 8- Ma (-0 + g)
6-
08
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 ⊟ Bdsorv`fgöa5 Os s`dghb quo oa v`rg`dmo ro`m v`mo5 ”mbk`rgtnb ho ua prbhuftb ho c`ftbros pbsgtgvbs os gku`m ` m` sun` ho mbs mbk`rgtnbs ho f`h` c`ftbr„, ² v`mhrà ost` prbpgoh`h oa mbs mbk`rgtnbs fbnpmoebs2, p`r` rospbahor f`mfumonbs5 ω
ω
ω
ω
?/8 ω
Ma g + Ma (-0 + g) > g ¾ + ma 4 + g ± . > ma 4 + g (¾ + ± . ) > ma 4 + g Ma Z g . (-0 + g)^ > Ma Z- g ‖ 0^ > ma | -0 ‖ g| + g @rk(-0 ‖g) > ma 4 - g ½ ω Ybr mb t`atb5
♣
Ma g + Ma (-0 + g) ≩ Ma Z g . (-0 + g)^
Cuafgbaos trgkbabnçtrgf`s o lgpordömgf`s
V`donbs quo sg ΰ os ro`m v`moa m`s gku`mh`hos 5 o ΰ > fbs ΰ + g soa ΰ g o ΰ > fbs ΰ - g soa ΰ g
fuy` sun` y rost` sba rospoftgv`noato5 rospoftgv`noato5 o ΰ + o
-gΰ
g
Hospoe`ahb
> 4 fbs ΰ , ogΰ - o-gΰ > g 4 soa ΰ .
fbs ΰ y soa ΰ ho ost`s õmtgn`s bdtoaonbs5 o gΰ ∔ o ∔ gΰ o gΰ + o ∔ gΰ , fba ΰ ro`m , soaΰ > fbs ΰ > 4g 4
Xoagoahb oa fuoat` quo ost`s oxprosgbaos, so hocgao5
♣
Fbsoab y om Voab ho ua aõnorb fbnpmoeb fbnpmoeb z5 o gz + o ∔ gz fbs z > , 4
o gz ∔ o ∔ gz soaz > 4g
Bdsorv`r quo sg z os ro`m, os hofgr sg z > x oatbafos om soa x , y` fbabfghbs ho m` v`rg`dmo ro`m.
fbs z y soa z fbgafghoa fba om fbs x y
@nd`s cuafgbaos sba `a`mîtgf`s oa tbhb om pm`ab fbnpmoeb pbr sor sun` y rost` ho `a`mîtgf`s y os soafgmmb vorgcgf`r quo 5 (fbs z)'> - soa z , (soa z)'> fbs z
@ftgvgh`h 75
∃
Eustgcgf`r quo mbs forbs ho m`s m `s cuafgbaos soa z y fbs z sba mbs ngsnbs quo mbs ho m`s cuafgbaos soa x y fbs x ho v`rg`dmo ro`m, ro`m, os hofgr prbd`r quo5 `)
d)
soa z > 9 ⇔ z > j ω + 9g , j > 9, ° 0, ° 4,….., fbs z > 9 ⇔ z > (¾
ω ω +
j
ω ω)
+ 9g , j >
° ° ° 9, 0, ° 4,….., 0?
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 ♣
X`akoato, fbt`akoato, sof`ato y fbsof`ato ho ua fbnpmoeb5 tk z >
soa z , fbs z
fbt k z >
0 0 0 , sof z > , fbs of z > tk z fbs z soa z
Om hbngagb ho f`h` ua` ho ost`s cuafgbaos sba tbhbs mbs fbnpmoebs quo ab `aum`a om hoabnga`hbr y tbh`s sba `a`mîtgf`s oa hgflbs hbngagbs.
♣
Voab lgpordömgfb lgpordömgfb y Fbsoab lgpordömgfb lgpordömgfb ho ua fbnpmoeb5 o z + o ∔ z o z ∔ o ∔ z sl z > , fl z > 4 4
Bdsorv`r quo sg z os ro`m y v`mo z > x oatbafos fl z y y` fbabfghbs ho m` v`rg`dmo ro`m.
sl z fbgafghoa fba om fl x y om sl x
@nd`s sba `a`mîtgf`s oa tbhb om pm`ab fbnpmoeb y v`mo quo 5
♣
(fl z)‗> sl z , (sl z)‗> fl z
Oxpbaoafg`m koaor`mgz`h` koaor`mgz`h` x
x ma `
Oa v`rg`dmo ro`m so hocgao ` > o hoabnga` oxpbaoafg`m koaor`mgz`h`.
p`r` ` 1 9 quo rosumt` sor ua` cuafgöa, ` m` quo so
Oa F so hocgao m` pbtoafg` koaor`mgz`h` ho n`aor` sgngm`r, porb ab rosumt` sor cuafgöa5 ♣
Ybtoafg` koaor`mgz`h` 5 `z > oz ma ` , fba ` ≩ 9
Vg oa m` oxprosgöa `atorgbr so tbn` m` r`n` prgafgp`m hom mbk`rgtnb, so bdtgoao ua` cuafgöa hoabnga`h` oxpbaoafg`m oxpbaoafg`m koaor`mgz`h` quo so hocgao pbr5 z
♣
z Ma `
Cuafgöa oxpbaoafg`m koaor`mgz`h`5 ` > o
, fba ` ≩ 9
• Oeorfgfgbs 04- Oxpros`r oa cbrn` dgaöngf` mbs sgkugoatos fbnpmoebs5 g /4
`) o ω
(6-ωg)/6
d) o
06- Nbstr`r quo5
f)ma(0 + g)
z
`) ma(o ) ≩ z
h) ma(-0)
ma z
d) o
o)
Ma ( 6 + g )
> z p`r` z ≩ 9
08- Oxpros`r oa cbrn` dgaöngf` mbs sgkugoatos fbnpmoebs5 03
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 `) fbs(-g)
soa( ω ∔ g )
d)
f) sl(0-g)
h) fl ( ¾ ωg)
0?- Honbstr`r5 -z
> 0/ oz o) soa z > soa z
o z > o z z h) o > fl z + sl z
gz
d) o
`)
f) o
> fbs z + g soa z c) soa(gz) > g sl z
03- Honbstr`r 5 `) soa(x + gy) > soa x fl y + g fbs x sl y f) sl(x + gy) > sl x fbs y + g fl x soa y
d) fbs(x + gy) > fbs x fl y - g soa x sl y h) fl(x + gy) > fl x fbs y + g sl x soa
y
0;- L`mm`r tbhbs mbs v`mbros ho z quo vorgcgf`a m`s sgkugoatos ofu`fgbaos ofu`fgbaos55 4z
`) o
gz
> -0
d) o
o) flz > -4
> 4
f)Ma z > g ω /8 z
c) fbs z > soa z
k) o
> 0 ‖ g
h) fbsz > 4g l) soa(gz) > sl z
0 g - soa( soa(gz) gz)
| z |4 + 4 d) k4(z) > 4 z + 4gz
f) k6(z) >
fbs z z
;- Cuafgbaos `rnöagf`s ♣ _a` cuafgöa k(x,y) ho hbs v`rg`dmos ro`mos so hgfo quo os
`rnöagf` oa ua hbngagb H sg 4 4 ∄ k ∄ k > 9, tgoao horgv`h`s sokuah`s fbatgau`s y vorgcgf` oa H m` ofu`fgöa hgcoroafg`m + 4 4 ∄y ∄x hoabnga`h` ofu`fgöa ho M`pm`fo.
⊟ Bdsorv`fgbaos5 `) M` ofu`fgöa ho M`pm`fo os gnpbrt`ato oa cîsgf` y` quo ostà fbaoft`h`, pbr oeonpmb, fba om cmueb ho f`mbr b ho cmughbs, b fu`mqugor sgston` `gsm`hb quo gavbmufro om fàmfumb ho cuafgbaos pbtoafg`mos. d) M` oxprosgöa
∄
4
k
∄x
4
+
4
k
∄y
4
∄
so hoabnga`
m`pm`fg`ab ho k(x,y) y os gatoros`ato bdsorv`r quo
rosumt` sor m` hgvorkoafg` hom kr`hgoato ho k y pbr ommb so suomo gahgf`r5 0;
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0
k ∄ 4k + 4 4 ∄y ∄x ∄
4
r
r
r
> hgv (kr` h k) > ∋ .(∋k) > ∋
4
k
Oeonpmb 6
4
k(x,y) > x ‖ 6xy os `rnöagf` p`r` tbhb p`r ho aõnorbs ro`mos puos5 kx > 6 x4 ‖ 6 y4 ⇔ kxx > 3 x , ky > ‖ 3 x y ⇔ kyy > - 3 x pbr mb t`atb
kxx + kyy > 3x ‖ 3 x > 9
Fbnb k s`tgsc`fo m` ofu`fgöa ho M`pm`fo y tgoao horgv`h`s sokuah`s fbatgau`s oatbafos `rnöagf` oa tbhb om pm`ab x,y.
k os
Α Xobron`- Fbahgfgöa aofos`rg` ho `a`mgtgfgh`h Vg c(z) > u(x,y) + g v(x,y) os `a`mîtgf` oa ua hbngagb H oatbafos m`s cuafgbaos u(x,y) y v(x,y) sba `rnöagf`s oa H.
Honbstr`fgöa Y`r` l`for ost` honbstr`fgöa v`nbs ` supbaor quo 5 sg c(z) os `a`mîtgf` oa H oatbafos oxgstoa m`s horgv`h`s sokuah`s ho m`s cuafgbaos u(x,y) y v(x,y) y sba fbatgau`s oa H, pbr ommb m`s horgv`h`s sokuah`s fruz`h`s sba gku`mos (uxy > uyx , vyx > vxy ) Nàs `hom`ato ost` supbsgfgöa sorà eustgcgf`h` fu`ahb vo`nbs quo ua` cuafgöa `a`mîtgf` `hngto horgv`h` ho tbhb brhoa y tbh`s sus horgv`h`s sba `a`mîtgf`s. Ybr sor c(z) `a`mîtgf` oa H , so funpmoa oa H m`s fbahgfgbaos (FT) 5 ux > vy y uy > - vx horgv`ahb m` prgnor` gku`mh`h rospoftb ho x y horgv`ahb h orgv`ahb m` sokuah` rospoftb ho y bdtoaonbs5
u x u y
v y ⇔ u xx > v yx > ∔ v x ⇔ u yx > ∔ v xy
>
y sun`ahb ngondrb ` ngondrb m`s m `s õmtgn`s gku`mh`hos bdtoaonbs5
uxx + uyy > vyx + (- vxy) > 9 pbr mb t`atb u(x,y) os `rnöagf` oa H. Topgtgoahb mbs p`sbs, porb horgv`ahb m` prgnor` rospoftb ` y y horgv` horgv`ahb ahb m` sokuah` rospoftb ho x y rost`ahb rost`ahb ngondrb ` ngondrb, so pruod` pruod` quo v(x,y) os `rnöagf` oa H.
⊟ Bdsorv`fgöa5
u(x,y) y v(x,y) sba `rnöagf`s oa H, ab os sucgfgoato p`r` `sokur`r quo m` cuafgöa c(z) > u(x,y) + g v(x,y) os `a`mîtgf` oa H. Ybr oeonpmb u(x,y) > x y v(x,y) > -y sba `rnöagf`s porb c(z) > u(x,y) u(x,y) + g v(x, v(x,y) y) > x ‖ gy > z ab os `a`mîtgf` oa agakõa puatb.
V`dor quo
0<
Nöhumb G _agh`h 0
N`tonàtgf` H y H0 ♣
Fbaeuk`h` `rnöagf`
Vg hbs cuafgbaos u(x,y) y v(x,y) sba `rnöagf`s oa H y s`tgsc`foa m`s fbahgfgbaos ho (F.T) oa H, so hgfo quo v(x,y) os fbaeuk`h` `rnöagf` ho u(x,y). X`ndgça puoho hofgrso `sî5 Vg c(z) > u(x,y) + v(x,y) os m` fbaeuk`h` `rnöagf` ho u(x,y).
g v(x,y) os `a`mîtgf` oa ua hbngagb H, oatbafos
Oeonpmbs 4
4
4
0- Fbnb c(z) > z > x ‖ y + g 4xy os `a`mîtgf` oa F , pbhonbs hofgr quo v(x,y) > 4xy os m` 4 4 fbaeuk`h` `rnöagf` ho u(x,y) > x ‖ y ²u(x,y) os m` fbaeuk`h` `rnöagf` ho v(x,y)2 4
4
Y`r` rospbahor hodonbs `vorgku`r sg v(x,y) + g u(x,y) > 4xy + g (x ‖ y ) os `a`mîtgf`. Ym`ato`ahb m`s fbahgfgbaos ho (F.T) toaonbs5 4y > -4y , 4x > - 4x . Fbnb sömb so s`tgsc`foa oa om brgkoa, ost` cuafgöa tgoao hbngagb ho `a`mgtgfgh`h v`fîb, pbr mb t`atb u(x,y) ab os m` fbaeuk`h` `rnöagf` ho v(x,y).
- u(x,y) os m` fbaeuk`h` `rnöagf` ho v(x,y), puos m` cuafgöa v(x,y) - g u(x,y) > 4xy + g (-x 4 + y4 ) os `a`mîtgf` oa F. Os gatoros`ato bdsorv`r quo
4- L`mm`r, sg os pbsgdmo, ua` cuafgöa v(x,y) ho nbhb quo c(z) > x ‖ 6y + o so` `a`mîtgf`.
4x
fbs y + g v(x,y)
u(x,y) > x ‖ 6y + o4x fbs y ab s`tgsc`fo m` ofu`fgöa ho M`pm`fo (fbnprbd`r quo uxx + uyy ≩ 9 ) oatbafos u(x,y) ab os `rnöagf` y pbr mb t`atb, rofbrh`ahb m` fbahgfgöa aofos`rg` ho `a`mgtgfgh`h, os gnpbsgdmo l`mm`r ua` cuafgöa `a`mîtgf` c(z) quo toak` ` u(x,y)
Fbnb
fbnb fbnpbaoato ro`m. 6- L`mm`r, sg os pbsgdmo, ua` cuafgöa v(x,y) ho nbhb quo c(z) > 4x ‖ 6y - o so` `a`mîtgf`. Oa osto oeonpmb m` p`rto ro`m os u(x,y) > 4x ‖ 6y - o mb t`atb m` p`rto ro`m ho c(z) os `rnöagf`. Puoronbs l`mm`r v(v,y) p`r` quo fbahgfgbaos ho (F.T)5
ux > vy
x
fbs y + g v(x,y)
x
fbs y , quo s`tgsc`fo uxx + uyy > 9 , pbr
c(z) so` `a`mîtgf`, pbr mb t`atb hodoràa vorgcgf`rso m`s
⇔ 4 - ox fbs y > vy
uy > - vx ⇔ -6 + ox soa y > - v x Ost`s ofu`fgbaos abs porngtoa fbabfor m`s hbs horgv`h`s p`rfg`mos ho prgnor` rospoftb ho m` v`rg`dmo y y n`atoagoahb x cge` oafbatr`nbs5
v(x,y), gatokr`ahb m`
x
x
v(x,y) > ∪ (4 ∔ o fbs y ) hy > 4y ‖ o soa y + k(x) hbaho k os ua` cuafgöa `rdgtr`rg` quo hopoaho h opoaho sömb ho x, os hofgr os fbast`ato rospoftb ho y 07
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0
x
V`donbs `lbr` quo v(x,y) > 4y ‖ o soa y + k(x) fuy` horgv`h` rospoftb ho x os5 vx > - ox soa y + k'(x) , `honàs pbr m` sokuah` ofu`fgöa ho (F.T) s`donbs quo vx > 6 ‖ ox soa y , pbr mb t`atb t `atb gku`m`ahb bdtoaonbs 5
ox soa y + k‗(x) > 6 ‖ ox soa y ⇔ k‗(x) > 6 ⇔ k(x) >
∪ 6 hx > 6x + j , hbaho j os ua`
fbast`ato `rdgtr`rg`. Toonpm`z`ahb osto v`mbr ho k(x) oa m` oxprosgöa ho v bdtoaonbs5
v(x,y) > 4y ‖ ox soa y + 6x + j Vo hoe` fbnb oeorfgfgb m` vorgcgf`fgöa quo c(z) os `a`mîtgf`.
>4x ‖ 6y - ox fbs y + g (4y ‖ o x soa y + 6x + j)
M` p`rto ro`m y m` p`rto gn`kga`rg` ho ua` cuafgöa `a`mîtgf` , `honàs ho sor `rnöagf`s vorgcgf`a ua` rom`fgöa ho brtbkba`mgh`h.
5
∃ @ftgvgh`h 09 Honbstr`r quo 5 Vg
c(z) > u(x,y) + g v(x,y) os `a`mîtgf` oa ua hbngagb H y Y9(x9 , y9) H u(x,y) > u(x , y ) > f , v(x,y) > v(x , y ) > j 9 9 9 9abrn`mos portoaofo ` oatbafos oa m`s Y furv`s agvomoatro mbs voftbros , so fbrt`a brtbkba`mnoato àakumb t`akoatos b mbs voftbros 9 (om ho ` `nd`s furv`s tr`z`hbs oa Y9 os roftb) @yuh`5 F`mfum`r om kr`hgoato ho `nd`s furv`s ho agvom oa Y9 y fbnprbd`r quo om prbhuftb osf`m`r oatro `ndbs os gku`m ` forb (us`r FT) y pbr mb t`atb mbs voftbros sba brtbkba`mos. Tofbrh`r quo 5 Vg ua` cuafgöa ho hbs v`rg`dmos k(x,y) os horgv`dmo oa ua hbngagb H oatbafos su kr`hgoato, quo so r
hocgao fbnb ∋k > k' x
(
(
g + k' y e , ov`mu`hb oa Y9 os ua
u(x,y)>u(x9,y9)
y9
v(x,y)>v(x9,y9) x9
voftbr abrn`m ` m` furv` ho agvom k(x,y) > k(x9 , y9) > f, sgonpro quo oa hgflb puatb om kr`hgoato ab so` aumb.
Oeonpmb
c(z) > z4 , y toagoahb oa fuoat` su oxprosgöa oqugv`moato 4 4 u(x,y) + g v(x,y) > x - y + g 4xy , m`s furv`s ho agvom ho su p`rto ro`m o gn`kga`rg` quo p`s`a pbr (x9 , y9) sba 5
H`h`
u(x ,y) > u(x9 , y9) ⇔ x4 - y4 > xb 4 - y9 4 , v(x , y) > v(x9 , y9) ⇔ 4xy > 4 x9 y9 4
4
Vg mm`n`nbs f > x b - y 9 y j > 4 x9 y9 oatbafos m`s furv`s ho agvom tgoaoa ofu`fgöa 4 4 u(x,y) > x - y > f y v(x,y) > 4xy > j , quo roprosoat`a lgpçrdbm`s. r ( ua voftbr ( Vg f`mfum`nbs om kr`hgoato ho f`h` furv` y mb ov`mu`nbs oa (x9 , y9) bdtoaonbs abrn`m ` f`h` ua` ho omm`s, oa osto f`sb mbs voftbros abrn`mos sba ∋u > 4x g ∔ 4y e ,
49
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 r
(
r
r
(
4y g + 4x e y sg mbs ov`mu`nbs oa (x9 , y9) y l`fonbs om prbhuftb osf`m`r bdtoaonbs ∋u( Y9 ).∋v( Y9 ) > (4x 9 g ∔ 4y 9 e ).(4y 9 g + 4x 9 e ) > 8x 9 y 9 ∔ 8y 9 x 9 > 9
∋v >
(
(
(
(
Fbnb mbs voftbros abrn`mos abrn`mos sba brtbkba`mos , m`s furv`s so fbrt`a brtbkba` brtbkba`mnoato mnoato oa Y9
• Oeorfgfgbs
49- Fbnprbd`r quo m`s sgkugoatos cuafgbaos sba `rnöagf`s oa tbhb T4 y fbastrugr ua` cuafgöa c(z) > u(x,y) + g v(x,y) quo so` `a`mîtgf` ∉z -x
4
`) u(x,y) > o fbs y + 4xy f) v(x,y) > fbs y (fl x + sl x)
4
d) u(x,y) > 6x ‖ 4 ‖ x + y 4 6 h) v(x,y) > 6x y ‖ y ‖ 8xy ‖ 6y + 0
40- L`mm`r, sg os pbsgdmo, pbsgdmo, ua` cuafgöa l(x,y) ho nbhb quo
c(z) so` `a`mîtgf` oa tbhb om pm`ab
`) c(z)
> l(x,y) + 4 y4 ‖ g xy
44- Vg
c(z) > u(x,y) + g v(x,y) os `a`mîtgf` oa z9 > ` + g d , honbstr`r quo ∋u(`, d ) ⊯ ∋v(`, d)
d) c(z)
> ToZz6 ‖ 4z ^ + g l(x,y) r
r
46- L`mm`r m`s furv`s ho agvom ho c(z), roprosoat`rm`s kràcgf`noato y fbnprbd`r su brtbkba`mgh`h oa mbs puatbs ho fbat`ftb5 4
`) c(z) > 6 z + 4g
f) c(z) > Ma z
d) c(z) > z
h) c(z) > 0/z
Oeorfgfgbs `hgfgba`mos
0-
Toprosoat`r kràcgf`noato mbs fbnpmoebs z quo vorgcgf`a m`s m `s rom`fgbaos sgkugoatos5 d) 0 ≨ z ∔ g = 8
` ) Gn(z) 1 4 To(z-4) h)
z = To( z )
o)
4 z
≯
f) z 1 To( z )
z-g
c)
z ∔ 0 = | z + g | = | z - 4g |
4- L`mm`r y kr`cgf`r om hbngagb ho horgv`dgmgh`h y ho `a`mgtgfgh`h ho m`s sgkugoatos cuafgbaos y f`mfum`r m` horgv`h` horgv`h` oa mbs puatbs hbaho hbaho oxgst` 4
`) C(z) > (4x ‖ y) (0 + gx) 4 4 f) L(z) > x {| z | + g y }
4
4
∔ 0 ∔ g g
`)
fbs(gz) > fl z
d) |soaz|
?- Honbstr`r5 40
+ 4y)
6
6- Fbacgrn`r quo5 `) Ma(-0 ‖ g) ‖ Ma g ≩ Ma
8- Honbstr`r quo
4
d) K(z) > 6x y + 4x + g (y ‖ 4 xy 6x h) J(z) > o ( fbs (6y) + g soa (6y))
d) Ma(g ) ≩ 6 Ma g 4
+ |fbs z|4 > 0 ⇘ z os ro`m
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0 `) Vg
soa (x + gy) > ` , hbaho ` os ua aõnorb ro`m quo vorgcgf` ‖0 ≨ ` ≨ 0 oatbafos soa (x + g y)> soa x , y pbr mb t`atb x > `rf soa ` + 4j ω , y > 9 d) Vg soa (x + gy) > d , hbaho d os ua aõnorb ro`m quo vorgcgf` d 1 0 oatbafos soa x > 0 y fl y > d , y pbr mb t`atb x > ω /4 + 4jω , y > `rk fl d f) Vg soa (x + gy) > f , hbaho f os ua aõnorb ro`m quo vorgcgf` f = -0 oatbafos soa x > -0 y fl y > -f , y pbr mb t`atb x > -ω /4 + 4jω , y > `rk fl (-f) 3- Vg c(z) > u(x,y) + g v(x,y) os `a`mîtgf` oa ua hbngagb cuafgbaos sba `a`mîtgf`s oa H `) k(z) > v(x,y) + g u(x,y)
H, `vorgku`r sg m`s sgkugoatos
d) l(z) > v(x,y) - g u(x,y)
;- Vg u(x,y) y v(x,y) sba `rnöagf`s oa `a`mîtgf` oa H.
H , honbstr`r quo c(z) > (ux + vy) + g (vx ‖ uy) os
44
Nöhumb G - _agh`h 0
N`tonàtgf` H y H0
N@XONÀXGF@ H y H0 Nöhumb G5 @aàmgsgs ho S`rg`dmo Fbnpmoe`
_agh`h 4
Xr`ascbrn`fgbaos N`k. N`rî` Gaçs D`r`k`ttg
♣ Xr`ascbrn`fgbaos _a` kr`a hgcoroafg` oatro m`s cuafgbaos ro`mos y m`s fbnpmoe`s rosgho oa su roprosoat`fgöa kràcgf`. Oa mbs prgnorbs fursbs ho `aàmgsgs n`tonàtgfb so suomo hohgf`r nuflb tgonpb oa ostuhg`r 4 m`s kràcgf`s ho m`s cuafgbaos ro`mos y > c(x) y z > c(x,y) , quo roprosoat`a furv`s ho T y 6 suporcgfgos ho T rospoftgv`noato. Ostb os gnpbsgdmo p`r` m`s cuafgbaos fbnpmoe`s ho v`rg`dmo fbnpmoe`, puostb quo om kràcgfb l`drî` quo sgtu`rmb oa ua osp`fgb ho fu`trb hgnoasgbaos ro`mos. Vga ond`rkb os pbsgdmo, gatoros`ato y õtgm h`r ua` roprosoat`fgöa kobnçtrgf` ho m`s cuafgbaos fbnpmoe`s ho v`rg`dmo fbnpmoe` fbnb `pmgf`fgbaos ho ua pm`ab (pm`ab z fba v`rg`dmos x,y) oa btrb pm`ab (pm`ab w fba v`rg`dmos u, v) Oa koaor`m m`s cuafgbaos w > c(z) tr`ascbrn`a ua rofgatb @ hom pm`ab fbnpmoeb z oa ua rofgatb D hom pm`ab fbnpmoeb w , pbr ommb so hgfo quo roprosoat`a ua` tr`ascbrn`fgöa kobnçtrgf` ho ua sudfbaeuatb ho F oa btrb sudfbaeuatb ho F.
y
w>c(z)
@
v D>c(@)
x Ym`ab
u
z
Ym`ab w
@atos ho l`for ua ostuhgb hot`mm`hb ho m`s tr`ascbrn`fgbaos nàs gnpbrt`atos, hocgagronbs m` fbnpbsgfgöa ho tr`ascbrn`fgbaos y om fbafoptb ho puatb cgeb ho ua` tr`ascbrn`fgöa.
0
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
♣ Fbnpbsgfgöa ho tr`ascbrn`fgbaos Vg w > c(z) tr`ascbrn` ua rofgatb @0 oa btrb D0 , y w > k(z) tr`ascbrn` D0 oa btrb rofgatb F0 oatbafos m` cuafgöa w > k(c(z)) , ` m` quo so hoabnga` (fbnb oa m` v`rg`dmo ro`m) fbnpbsgfgöa ho
m`s tr`ascbrn`fgbaos c y k , tr`ascbrn` om rofgatb @0 oa om rofgatb F0. y
w* >c(z)
@0
v*
w >k(w*)
D0
x
v
F0
u* Ym`ab w
Ym`ab z
u Ym`ab w
w >k(c(z)) Oeonpmbs5
0- H`h`s m`s cuafgbaos c(z) > so gahgf`a ` fbatgau`fgöa5
6z + g , k(z) > z4 , pbhonbs fbnpbaorm`s ho m`s hbs n`aor`s quo
k(c(z)) > k(6z + g) > (6z + g) 4 > 7z4 +3gz ‖0
,
c(k(z)) > c(z4) > 6z4 + g
fbnb mbs rosumt`hbs sba hgstgatbs, pbhonbs `sokur`r quo m` fbnpbsgfgöa, oa koaor`m, ab
os
fbanut`tgv`. 4- H`h`s m`s cuafgbaos su fbnpbsgfgöa os 5
c(z) > oz - 0, ho hbngagb F, y k(z) > Ma z, ho hbngagb F ‖ {9},
k(c(z)) > k(oz - 0) >Ma (oz - 0) , fuyb hbngagb os F ‖ {4jωg , j > 9, °0, °4 …} puos o4jωg ‖0 > 9 y Ma 9 ab oxgsto c(k(z)) >c(Ma z) > oMa z - 0 > z - 0 , fuyb hbngagb os F ‖ {9} puos Ma 9 ab oxgsto y oMa z > z
♣ Yuatbs cgebs ho ua` tr`ascbrn`fgöa Vg m` gn`koa ho ua fbnpmoeb z9 pbr ua` cuafgöa w > c(z) vorgcgf` quo c(z9) > z9 , so hgfo quo z9 os ua puatb cgeb ho m` tr`ascbrn`fgöa tr`ascbrn`fgöa c.
Oeonpmbs5
0- Y`r` l`mm`r mbs puatbs cgebs ho m` tr`ascbrn`fgöa c 0(z) > (0 - 4g) 4g) z ‖ 8 , so pm`ato` c 0(z9) > z9, bdtoagoahb oa osto f`sb m` ofu`fgöa (0 - 4g) z9 - 8 > z9 , fuy` sbmufgöa os z9 > - 4/ g > 4g . Om fàmfumb c 0(4g) > (0 - 4g) 4g ‖ 8 > 4g + 8 ‖ 8 > 4g abs vorgcgf` quo z9 > 4g os puatb cgeb ho c 0 . 4
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
4- Y`r` l`mm`r mbs puatbs cgebs ho m` tr`ascbrn`fgöa c 4(z) > 0/ z, so pm`ato` c 4(z9) > z9 , bdtoagoahb oa osto f`sb m` ofu`fgöa 0/ z9 > z9 , fuy`s sbmufgbaos sba z9 > °0 : pbr mb t`atb c 4 tgoao hbs puatbs cgebs, om 0 y om ‖0. 6- Os gatoros`ato bdsorv`r quo m` cuafgöa ghoatgh`h fbnb puatbs cgebs.
c(z) > gh(z) > z tgoao tbhbs mbs fbnpmoebs
0- Xr`ascbrn`fgöa mgao`m5 w > @z + D Y`r` `a`mgz`r m` tr`ascbrn`fgöa w >@z + D , hbaho @ y D sba aõnorbs aõnorbs fbnpmoebs fbnpmoebs ab aumbs, os fbavoagoato fbasghor`r prgnorb m`s cuafgbaos c(z) > @ z y k(z) > z + D puos su fbnpbsgfgöa rosumt` k(c(z)) >k(@z) > @z + D > w. Ybr ommb `a`mgz`nbs ` fbatgau`fgöa ost`s hbs tr`ascbrn`fgbaos pbr sop`r`hb.
`) Xr`ascbrn`fgöa w > @ z , @≩9 H`h` m` cuafgöa w > c(z) > @ z , rosumt` ovghoato quo c(9) > 9, pbr ommb 9 os ua puatb cgeb. Vg z ≩ 9 y @ os ua fbnpmoeb ho nöhumb ` y `rkunoatb ΰ , os hofgr nöhumb y om `rkunoatb ho su gn`koa w vorgcgf`a5
|w|>|@ z|>|@||z|>`|z| `rk(w) > `rk(@ z) > `rk(@) + `rk(z) > ΰ + `rk(z)
⇔ ⇔
@ > ` ogΰ , oatbafos om
|w|>`|z| `rk(w) > ΰ + `rk(z)
Ybr mb t`atb m` tr`ascbrn`fgöa w > @ z fbasgsto oa ua` rbt`fgöa fba foatrb oa om brgkoa h`h` pbr om àakumb ΰ > `rk(@) y su nöhumb hopoaho hom nöhumb ho @5 sg | @ | > ` > 0, om fbnpmoeb w tgoao gku`m nöhumb quo z y hofgnbs quo fbasorv` m`s hgst`afg`s. `g ` 1 0, om fbnpmoeb w tgoao nöhumb n`ybr quo z y hofgnbs quo l`y ua` hgm`t`fgöa, sg
` = 0, om fbnpmoeb w tgoao nöhumb noabr quo z y hofgnbs quo l`y ua` rohuffgöa, w > `r og (μ + ΰ) gμ y z>r o w > @z v μ + ΰ μ D
u
x Ym`ab w
Ym`ab z Oeonpmbs5
6
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
0- M` gn`koa ho ua fbnpmoeb z ho nöhumb
6 y `rkunoatb ω /3 pbr m` tr`ascbrn`fgöa w > (0- g) z, hbaho @ > 0- g tgoao `rkunoatb - ω /8 y nöhumb 4 , os ua fbnpmoeb w fuyb nöhumb os 6 4 y fuyb `rkunoatb os ω /3 + (- ω /8) > - ω /04 4- M` gn`koa ho m` cr`ae` gacgagt` hocgagh` pbr {(x,y) / x = y = x + 0} pbr m` tr`ascbrn`fgöa w > 4gz , hbaho @ > 4g tgoao `rkunoatb ω /4 y nöhumb 4 , os t`ndgça ua` cr`ae` gacgagt` quo so bdtgoao rbt`ahb, f`h` fbnpmoeb ho hgfl` cr`ae`, ω /4 r`hg`aos fba rospoftb `m brgkoa y numtgpmgf`ahb su nöhumb pbr 4. Os gatoros`ato bdsorv`r quo m` hgst`afg` oatro m`s hbs roft`s quo mgngt`a m` cr`ae` h`h` os 4 , pbr mb t`atb m` hgst`afg` oatro m`s hbs roft`s ho m` cr`ae` gn`koa os 4 4 > 4,
x
u
Ym`ab z
Ym`ab w
Vg so hoso` l`mm`r m`s ofu`fgbaos ho m`s roft`s quo mgngt`a m` cr`ae` gn`koa puoho tr`d`e`rso m` tr`ascbrn`fgöa oa cbrn` dgaöngf` fbnb so nuostr` ` fbatgau`fgöa5
(u + gv)g v u w wg > ∔ g ⇔ w > 4gz ⇔ z > > ∔ ⇔ x + gy > ∔ 4 4 4 4g 4 Ybr mb t`atb m` gn`koa ho m` roft` y m` gn`koa ho m` roft`
y > x os
y > x + 0 os ∔
u 4
>
∔
v
x > v / 4 y > ∔ u / 4
u v > b su oqugv`moato v > -u 4 4
+ 0 b su oqugv`moato v > - u - 4
4
d) Xr`sm`fgöa5 w > z + D H`hb quo m` cuafgöa w > z + D os ua` sun` ho fbnpmoebs, ab fbavgoao `a`mgz`rm` dusf`ahb su `rkunoatb y su nöhumb, fbnb oa om f`sb `atorgbr, sgab dusf`ahb su p`rto ro`m o gn`kga`rg`5
To(w) > To(z) + To(D) Gn(w) > Gn(z) + Gn(D) G n(D) Vg
D > d0 +g d4 , om fbnpmoeb w vorgcgf`5 To(w) > To(z) + d0 8
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Gn(w) > Gn(z) + d4 Ybr mb t`atb m` tr`ascbrn`fgöa w > z + D fbasgsto oa ua` tr`sm`fgöa ho d0 uagh`hos oa hgroffgöa `m oeo ro`m y d4 uagh`hos oa hgroffgöa `m oeo gn`kga`rgb, b ua` tr`sm`fgöa gku`m ` D.
y
v
z
w>z+D
w>z+D
z
D
D
D
u
x Ym`ab z
Ym`ab w
Oeonpmbs5
0- M` gn`koa hom fbnpmoeb
z > 6 ‖ 8g pbr m` tr`ascbrn`fgöa w > z ‖ ? + 4g , os om fbnpmoeb
w > (6 ‖ ?) + g (-8 + 4) > -4 ‖ 4 g
4- Y`r` oafbatr`r m` gn`koa hom àakumb y ≨ ¾ x - 0 , x ≯ 0 pbr m` tr`ascbrn`fgöa w > z ‖ hodonbs tr`sm`h`r f`h` fbnpmoeb 4 uagh`hos l`fg` m` gzqugorh` y 0 uagh`h l`fg` `rrgd`.
4+g
v y
w>z-4+g
(-0, ¾ )
x
u
(0,- ¾ ) Vg quoronbs l`mm`r su gn`koa `a`mîtgf`noato prbfohonbs ho m` sgkugoato n`aor`5 Hospoe`nbs z ho m` oxprosgöa w > z ‖ 4 + g , bdtoagoahb z > w + 4 ‖ g . Vg fbasghor`nbs z > x + g y y w > u + g v oatbafos roonpm`z`ahb oa m` õmtgn` oxprosgöa bdtoaonbs5
x > u + 4 x + g y > u + g v + 4 - g > (u + 4) + g ( v - 0) , ho hbaho y > v ∔ 0 Ybr mb t`atb5 Vg y ≨ ¾ x - 0 Vg x ≯ 0
⇔ v ‖ 0 ≨ ¾ (u + 4) - 0 ⇔ v ≨ ¾ u + 0 ⇔ u + 4 ≯ 0 ⇔ u ≯ -0
?
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Os gnpbrt`ato bdsorv`r quo m` gn`koa bdtoagh` `a`mîtgf`noato fbgafgho fba m` bdtoagh` kràcgf`noato `m fbngoazb hom oeorfgfgb.
f) Tbtbtr`sm`fgöa5 w > @z + D Vg fbasghor`nbs m`s cuafgbaos5
z* > c 0(z) > @z, quo roprosoat` ua` rbt`fgöa, y w > c 4(z*)> z* + D , quo roprosoat` ua` tr`sm`fgöa, y l`mm`nbs m` fbnpbsgfgöa oatro `nd`s bdtoaonbs5
w > c 4(c 0(z))> c 4(@z)> @z + D ♣ M` tr`ascbrn`fgöa w > @z + D so hoabnga` t`ndgça tr`ascbrn`fgöa mgao`m y pbhonbs `cgrn`r, oa d`so `m `aàmgsgs `atorgbr, roprosoat` ua` rbtbtr`sm`fgöa puos fbasgsto oa ua` rbt`fgöa h`h` pbr `rk(@) y ua` hgm`t`fgöa b fbatr`ffgöa h`h` pbr | @ | sokugh` ho ua` tr`sm`fgöa gku`m ` D. Oa p`rtgfum`r5 M` gn`koa ho ua` roft` hom pm`ab z pbr ua` tr`ascbrn`fgöa mgao`m os ua` roft` hom pm`ab w, m` gn`koa ho ua` fgrfuacoroafg` hom pm`ab z pbr ua` tr`ascbrn`fgöa mgao`m os ua` fgrfuacoroafg` hom pm`ab w, otf.
Oeonpmbs5
0- Vg quoronbs l`mm`r m` gn`koa hom fîrfumb T5 | z ‖ g | ≨ 4 pbr m` tr`ascbrn`fgöa w > (4 ‖ g) z - 6g , s`donbs quo su gn`koa sorà ua auovb fîrfumb quo so bdtgoao rbt`ahb (rospoftb hom brgkoa) f`h` puatb ho T ua àakumb @rk( 4 ‖ g) > `rftk (-0/4) , n`kagcgf`ahb m` hgst`afg`s
| 4 ‖ g | > ? y pbr õmtgnb tr`sm`h`ahb f`h` puatb 6 uagh`hos l`fg` `d`eb.
Vg gatoros` s`dor ox`ft`noato fuàm os m` gn`koa ho quo oa osto f`sb rosumt` sor
z>
T, so hospoe` z ho m` tr`ascbrn`fgöa h`h`,
w + 6g , y roonpm`z`ahb osto v`mbr oa m` hocgagfgöa hom 4∔g
T, so bdtgoao5 w + g ∔0 w + 6g ∔ g ( 4 ∔ g ) w + 6g ≨ 4 ⇔ | w ‖0 + g | ≨ 4 ? ≨ 4 ⇔ ∔ g ≨ 4 ⇔ 4∔g 4∔g 4∔g
fbaeuatb
pbr mb t`atb m` gn`koa hom fîrfumb T os ua fîrfumb foatr`hb oa (0,-0) ho r`hgb 4
?.
4- L`mm`r ua` cuafgöa mgao`m quo tr`ascbrno om trgàakumb roftàakumb mgngt`hb pbr m`s roft`s y > - 4x -0, y > ¾ x -0, y > - x + 4 oa btrb trgàakumb ghçatgfb porb fba om f`totb noabr `pby`hb oa om oeo lbrgzbat`m pbsgtgvb y om f`totb n`ybr fbatoaghb oa om oeo vortgf`m pbsgtgvb. 3
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
v
y
w > c(z) > 2 x u quo om Xoagoahb oa fuoat` om kràcgfb `atorgbr , fbnoaz`nbs tr`sm`h`ahb om trgàakumb ho nbhb àakumb roftb toak` su vçrtgfo oa om brgkoa, os hofgr sudgnbs om trgàakumb ua` uagh`h, p`r` ommb `pmgf`nbs w* > c 0(z) > z + g . Oa om pm`ab pm`ab w* m`s poahgoatos ho m`s roft`s quo mgngt`a om auovb trgàakumb sba gku`mos ` m`s ho m`s roft`s h`h`s5 - 4, ¾ , -0. y
v*
w* > c 0(z) > z +g
ΰ x
u*
Ym`ab z Ym`ab w* Vg ΰ os om àakumb ho gafmga`fgöa ho m` roft` quo tgoao poahgoato ¾ , s`donbs quo tk ΰ > ¾ . Vg ocoftu`nbs ua` rbt`fgöa oa soatghb ho m`s `kue`s hom rombe ho `npmgtuh ΰ , os hofgr sg fbasghor`nbs ua fbnpmoeb ho `rkunoatb -ΰ , m` tr`ascbrn`fgöa w > o-g ΰ w* rbt`rà tbhb om trgàakumb y mb mmov`rà ` m` pbsgfgöa quo abs gatoros`.
¾ , , ²fuàm os om fbnpmoeb o-g ΰ > fbs ΰ - g soa ΰ2 Vo hoe` fbnb oeorfgfgb vorgcgf`r quo 4∔g . o ∔gΰ > ? 4 ∔ g Ybr mb t`atb m` rbt`fgöa quo hodo ro`mgz`rso ostà h`h` pbr m` cuafgöa w > c 4(w*) > w* ? L`fgoahb m` fbnpbsgfgöa oatro c 0 y c 4 pbhonbs `sokur`r quo m` tr`ascbrn`fgöa pohgh` os Vg tk ΰ >
w > c 4(c 0(z)) > c 4(z + g) > 4 ∔ g ( z + g ) > 4 ∔ g z + 0 + g 4 , quo fbnb so bdsorv` os ua` ? ? ? ? rbtbtr`sm`fgöa.
v
y
w* > c 0(z) > z +g
v*
w > c 4(z) > (4 -g) w*/ ? ΰ
x
u*
Ym`ab z
Ym`ab w* 4 0 4 ∔ g z + +g ; ? ? ?
u
Ym`ab w
w >
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
• Oeorfgfgbs 0- H`h` m` tr`ascbrn`fgöa w > (0 ‖ g) z + 4g , l`mm`r y kr`cgf`r m` gn`koa ho5 `) m` roft` ho ofu`fgöa f) m` fgrfuacoroafg` | z
y>¾x+4 - g |> 4
d) om songpm`ab x ≨ 0 h) om trgàakumb ho vçrtgfos
g , -0 + g , -0
4- L`mm`r ua` tr`ascbrn`fgöa mgao`m quo5 `) oavîo om puatb z0 > -g oa w0 > 0 y z4 > 0 + 4g oa w4 > -4g gω /6 -gω /3 d) oavîo om puatb z9 > 6 o oa w9 > 4 o y toak` ` z0 > -g fbnb puatb cgeb f) oavîo m` fgrfuacoroafg` | z ‖ 4g| > 6 oa m` fgrfuacoroafg` | w + 0 | > ? 6- H`h` c(z) > @z + D , honbstr`r quo5 `) Vg z9 os puatb cgeb ho c(z) oatbafos c(z) puoho osfrgdgrso fbnb c(z) > @ (z - z9) + z9 , pbr mb t`atb c(z) roprosoat` ua` rbt`fgöa `mrohohbr hom puatb cgeb z9 d) |c(z0) ‖ c(z4)| > | @ | | z0 ‖ z 4| , pbr mb t`atb sg h os m` hgst`afg` oatro hbs puatbs hom pm`ab z, m` hgst`afg` oatro sus gnàkoaos rosumt` sor om prbhuftb | @ | . h
4. Gavorsgöa5 w >
0 z
w > 0/z so hoabnga` gavorsgöa y ost`dmofo ua` fbrrospbahoafg` puatb ` z w z> 9 puatb oatro puatbs hom pm`ab y puatbs hom pm`ab , oxfoptb p`r` , quo ab tgoao gn`koa y w > 9, quo ab os gn`koa ho agakõa fbnpmoeb hom pm`ab z. M` tr`ascbrn`fgöa
Vg z ≩9 , pbhonbs f`mfum`r su nöhumb y su `rkunoatb5
|w|>0/|z| `rk(w) > `rk(0/z) > `rk(0) - `rk(z) > - `rk(z) Ostb abs porngto hofgr quo, sg z tgoao nöhumb 6 y `rkunoatb ω /8 , su gn`koa tgoao nöhumb `rkunoatb - ω /8
0/6 y
Oeonpmbs5
<
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
0- L`mm`r y kr`cgf`r m` gn`koa hom fîrfumb `dgortb
| z ‖ 4 | = 4 pbr w > 0/z
Vg w > 0/z oatbafos
z > 0/w y p`r` l`mm`r m` gn`koa ho | z ‖ 4 | = 4 roonpm`z`nbs z oa cuafgöa 0 ∔ 4w 0 ∔ 4w 0 = 4 ⇔ 0 4w 4 w ⇔ ho w hom sgkugoato nbhb5 4 ⇔ 4 4 ⇔ ∔ = w = w = w∔ = 4 4 4 4 4 4 |0 ‖ 4u ‖ g 4v| = 8 |u + gv| ⇔ (0 ‖ 4u) + 8 v = 8 (u + v ) ⇔ 0 ‖ 8u = 9 ⇔ u 1 ½ Ybr mb t`atb m` gn`koa hom fîrfumb `dgortb os ua songpm`ab fbnb so nuostr` oa om sgkugoato hgdueb5
y
v
w > 0/z x
0/8
4- L`mm`r o ghoatgcgf`r m` gn`koa ho m` roft`
u
4 x - y > 0 pbr w > g/z
Oa osto oeorfgfgb, oa om quo om h`tb os ua` ofu`fgöa oa v`rg`dmos x o y , os fbavoagoato tr`d`e`r mbs fbnpmoebs oa m` cbrn` dgaöngf` fbnb so nuostr` ` fbatgau`fgöa5
g g g(u - gv) v + gu v u w > ⇔ z > ⇔ z > 4 > 4 ⇔ x > 4 , y > 4 4 4 4 z w u +v u +v u +v u + v4
oatbafos m` gn`koa ho m` roft`
4v u ∔ 4 > 0 . 4 u + v u + v4
4 x - y > 0 os
4
4
4
Vg so fbasghor` m` ofu`fgöa oqugv`moato 4v ‖ u > u + v y so fbnpmot`a fu`hr`hbs, so bdtgoao (u + ¾ )4 + (v ‖ 0)4 > ?/8 quo roprosoat` ua` fgrfuacoroafg` fba foatrb oa om puatb (- ¾ , 0) y r`hgb ? 4
∃ @ftgvgh`h 05 `) Eustgcgf`r quo m` m ` tr`ascbrn`fgöa w > g/z puoho poas`rso fbnb m` fbnpbsgfgöa ho ua` gavorsgöa w* > c 0(z) > 0/z y ua` rbt`fgöa c 4 (w*) > g w* . d) Vo hoe` fbnb oeorfgfgb vorgcgf`r, utgmgz`ahb m` fbnpbsgfgöa noafgba`h` oa `), quo m` gn`koa ho m` roft` 4x - y > 0 os m` fgrfuacoroafg` gahgf`h` oa om oeonpmb `atorgbr. ²Fuàm ho mbs hbs nçtbhbs os nàs soafgmmb2
Α Xobron` 7
Nöhumb G _agh`h 4
N`tonàtgf` H y H0
`) M` gn`koa ho ua` fgrfuacoroafg` pbr m` tr`ascbrn`fgöa w > 0/z os ua` fgrfuacoroafg` b ua` roft`. d) M` gn`koa ho ua` roft` pbr m` tr`ascbrn`fgöa w > 0/z os ua` fgrfuacoroafg` fgrfuacoroafg ` b ua` roft`.
Honbstr`fgöa5 Puoronbs l`mm`r m` gn`koa pbr fbasghoronbs m` ofu`fgöa
w > 0/z ho ua` fgrfuacoroafg` fu`mqugor` hom pm`ab z , p`r` ommb
@x4 + @ y4 + D x + F y + H > 9
(0)
quo roprosoat` ua` fgrfuacoroafg` sg @ ≩ 9 y roprosoat` ua` roft` sg @ > 9 Y`r` l`mm`r su gn`koa hodonbs tr`t`r ho oxpros`r x o y oa cuafgöa ho u y v y pbr mb t`atb os fbavoagoato fbasghor`r m` tr`ascbrn`fgöa gavors` z > 0/w y bpor`r fbnb so nuostr` ` fbatgau`fgöa5
w > 0 ⇔ z > 0 ⇔ x + gy > 0 > (u - gv) > u4 - gv 4 ⇔ x > 4 u 4 , y > 4∔ v 4 u + gv (u - gv)(u - gv) u + v w z u +v u +v Toonpm`z`ahb mbs v`mbros ho x o y oa m` ofu`fgöa (0) bdtoaonbs5 4
4
u v ∔ v u @ + ∔ + H > 9 @ D F + 4 4 4 4 4 4 4 4 + + u v u v u v u v + + ost` y` os m` gn`koa quo dusf`nbs porb bdsorv`ahb fba fugh`hb vonbs quo oa `mkuabs tçrngabs `p`rofoa m`s v`rg`dmos u y v omov`h`s ` m` pbtoafg` fu`rt` y pbr mb t`atb os hgcîfgm rofbabfor quç furv` os. Vg s`f`nbs @ c`ftbr fbnõa oatro mbs hbs prgnorbs tçrngabs m` oxprosgöa `atorgbr tbn` m` cbrn`5
u4 + v4 u v + ∔ + H > 9 @ 4 D F 4 4 4 4 4 4 + + u v u v (u + v ) oatbafos pbhonbs sgnpmgcgf`r oa om prgnor tçrngab y porhor ho oso nbhb m`s pbtoafg`s fu`rt`s quoh`ahb
@
0 4
u +v
numtgpmgf`hb tbh` m` oxprosgöa pbr
4
+ D
u 4
u +v
∔F
4
v 4
u + v4
+H > 9
u4 + v4 ,bdtoaonbs m` gn`koa quo dusfàd`nbs5
@ + D u - F v + H u4 + H v4 > 9 09
(4)
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Y`r` fbnpmot`r m` honbstr`fgöa roquorgh` to prbpbaonbs m` sgkugoato `ftgvgh`h 5
∃ @ftgvgh`h 45 Fbnpmot`r om sgkugoato fu`hrb toagoahb oa fuoat` quo (4) os m` gn`koa ho fbafmugr quo m`s `cgrn`fgbaos ` ) y d) hom tobron` sba fbrroft`s.
sg M` ofu`fgöa (0) roprosoat`5 @ ≩ 9 ua` fgrfuacoroafg` quo ab p`s` pbr om brgkoa H ≩ 9 @ ≩ 9 H>9 @>9 H ≩ 9 @ > 9 ua` roft` quo p`s` pbr om brgkoa H>9
(0) pbr w > 0/z y
M` ofu`fgöa (4) roprosoat`5 ua` fgrfuacoroafg` quo ab p`s` pbr om brgkoa
• Oeorfgfgbs 8- H`h` m` tr`ascbrn`fgöa w > 0/z , l`mm`r y kr`cgf`r m` gn`koa ho5 `) om sokuahb fu`hr`ato f) om fu`hr`hb mgngt`hb pbr m`s roft`s
| y | + | x | >0
d) m` fgrfuacoroafg` | z + 0 |> 4 h) om fbaeuatb {(x,y) / ‖ x ≨ y ≨ 4x }
?- Honbstr`r quo m` gn`koa hom songpm`ab y 1 j , fba j 1 9 , pbr fgrfuacoroafg` .² Fuàm os m` gn`koa sg j os forb b aok`tgvb2.
w > 0/z os om gatorgbr ho ua`
3- Eustgcgf`r quo w > 0/(z ‖ z9) tr`ascbrn` ` m`s roft`s y ` m`s fgrfuacoroafg`s hom pm`ab z quo p`s`a pbr z9 oa roft`s hom pm`ab w. ;- L`mm`r m` gn`koa hom fbaeuatb {z /
| z ‖ g | = 0 , |z + 0| 1 0} pbr w > g / z
6. Xr`ascbrn`fgöa mgao`m cr`ffgba`rg`5 w >
`z + d fz + h
♣ Vg `, d, f y h sba aõnorbs fbnpmoebs quo vorgcgf`a
`.h ‖ d.f ≩ 9 , so hoabnga` `z + d . tr`ascbrn`fgöa mgao`m cr`ffgba`rg` (XMC) ` w > c ( z ) > fz + h
Muokb ho ost` hocgagfgöa surkoa `mkua`s prokuat`s prokuat`s , quo prosoat`nbs oa m` sgkugoato `ftgvgh`h.
∃ @ftgvgh`h 65 00
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
H`h`
`z + d , eustgcgf`r mbs sgkugoatos îtons y rospbahor toagoahb oa fuoat` m`s fz + h
w > c ( z ) >
gahgf`fgbaos quo so h`a oa f`h` f`sb5 fbnprbd`r quo m` tr`ascbrn`fgöa roprosoat` ua` rbtbtr`sm`fgöa. 0- Vg f >y` 9 so Fbnb l` hgsfutghb om fbnpbrt`ngoatb ho ost` õmtgn`, v`nbs ` supbaor quo f ≩ 9
4- ²Ybrquç so oxgko oa m` hocgagfgöa ho ost` tr`ascbrn`fgöa quo `.h ‖ d.f ≩ 9 2 Y`r` rospbahor os fbavoagoato l`for m` hgvgsgöa oatro om aunor`hbr y om hoabnga`hbr, y` quo pbr sor pbmgabngbs hom ngsnb kr`hb m` hgvgsgöa os pbsgdmo
---
`z+d ` z + `h/f d - `h/f
fz + h `/f
Fbnprbd`r quo sg `h ‖ df > 9 , oatbafos om rostb ho m` hgvgsgöa v`mo forb y c(z) > `/f (fbast`ato) , pbr mb t`atb fu`mqugor fbaeuatb hom pm`ab z so tr`ascbrn` tr`ascbrn` oa om fbnpmoeb `/f y f`rofo ho gatorçs.
6- Vg `.h ‖ d.f ≩ 9 y mm`n`nbs N `m rostb ho m` hgvgsgöa `atorgbr y mm`n`nbs A `m fbfgoato `/f, eustgcgf`r quo m` tr`ascbrn`fgöa mgao`m cr`ffgba`rg` puoho osfrgdgrso fbnb5
+ c ( z ) > `z d > A + N fz + h fz + h
N , hbaho N y A sba fbast`atos fbnpmoe`s, y fz + h fbasghor`ahb m`s cuafgbaos c 0(z) > fz + h , c 4(z) > 0/z , c 6(z) > A + Nz quo roprosoat`a, rospoftgv`noato, ua` tr`ascbrn`fgöa mgao`m, ua` gavorsgöa y btr` tr`ascbrn`fgöa mgao`m, eustgcgf`r
8- Xoagoahb oa fuoat` quo
c ( z ) > A +
quo m` tr`ascbrn`fgöa mgao`m cr`ffgba`rg` os ua` fbnpbsgfgöa ho ost`s tr`ascbrn`fgbaos, os hofgr f`mfum`r c 6( c 4( c 0(z))) y fbnprbd`r quo su rosumt`hb os gku`m ` c(z).
Oeonpmbs5
0- H`h`
w>
`) Fbnb
w>
z z∔g z z∔g
, l`mm`r m` gn`koa ho
⇔
`) m` fgrfuacoroafg`
|z| > 0 , d) om songpm`ab y ≯ 4x
w (z ‖ g) > z ⇔ wz - z > gw ⇔ z (w - 0) > gw ⇔ z >
gw w ∔0
gw > 0 ⇔ | g | | w | > |w |w - 0| ⇔ 0. |u + g v| > |(u ‖ 0) + g v| ⇔ w ∔0 u4 + v4 > (u ‖ 0)4 + v4 ⇔ u4 + v4 > u4 ‖4u + 0 + v4 ⇔ u > ¾ M` gn`koa ho
|z | > 0 os
Ybr mb t`atb m` gn`koa ho m` fgrfuacoroafg` | z | > 0 os m` roft` ho ofu`fgöa u > ¾
04
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
y ≯ 4x , toaonbs quo oxpros`r x o y fbnb cuafgbaos gw g(u + gv) numtgpmgf`ahb numtgpmgf`ahb pbr om ⇔ x + gy > ho u y v , pbr ommb fbasghor`nbs z > w ∔0 u + gv ∔ 0 d) Y`r` l`mm`r m` gn`koa hom songpm`ab
fbaeuk`hb hom hoabnga`hbr o gku`m`ahb m`s p`rtos ro`mos o gn`kga`rg`s so bdtgoao5
x>
v u4 + v4 ∔ u , , > y (u ∔ 0) 4 + v 4 (u ∔ 0) 4 + v 4
u4 + v4 ∔ u 4v pbr mb t`atb m` gn`koa hom songpm`ab y ≯ 4x os ≯ 4 4 (u ∔ 0) + v (u ∔ 0) 4 + v 4 b su oqugv`moato u4 + v4 ‖ u ‖ 4v ≯ 9 y fbnpmot`ahb fu`hr`hbs so bdtgoao 4 4 (u ‖ ¾ ) + (v ‖ 0) ≯ ?/8 quo roprosoat` om oxtorgbr hom fîrfumb ho foatrb ( ¾ ,0) y r`hgb ? / 4 ∃ @ftgvgh`h 85 `z + d , fba `.h ‖ d.f ≩ 9 fz + h 0- L`mm`r mbs puatbs cgebs ho c(z) y hofgr fuàatbs puatbs cgebs puoho toaor. 4- Vg abs hgfoa quo m` XMC c(z) tgoao tros puatbs cgebs, os hofgr oxgstoa tros puatbs t`m quo quo ` > h , d > f > 9 y pbr mb t`atb c(z) > z c(z0) >z0 , c(z4) >z4 y c(z6) >z6 , eustgcgf`r quo H`h`
c (z ) >
6- Eustgcgf`r quo m` fbnpbsgfgöa ho hbs XMC os ua` XMC. Fbasghor`r
c 4 (z ) >
c 0 ( z ) >
`0z + d0 y f0 z + h0
`4z + d4 , fbnpbaorm`s y bdsorv`r su cbrn`tb. f4z + h 4
8- Eustgcgf`r quo " tbh` XMC tr`ascbrn` m`s roft`s oa roft`s b fgrfuacoroafg`s y tr`ascbrn` m`s fgrfuacoroafg`s oa roft`s b fgrfuacoroafg`s". (Xoaor oa fuoat` quo y` so l` vgstb oa m` `ftgvgh`h 6, puatb 8, quo ua` XMC os fbnpbsgfgöa ho tr`ascbrn`fgbaos y` ostuhg`h`s).
z ≩ ∔ h , eustgcgf`r quo m` tr`ascbrn`fgöa w > `z + d `hngto fbnb gavors` ` z > ∔ hw + d , fw ∔ ` fz + h f ` p`r` w ≩ ≩ . (p`r` l`mm`r m` gavors`, sgnpmonoato l`y quo hospoe`r z oa cuafgöa ho w) . Ybr f ommb pbhonbs `cgrn`r quo m` tr`ascbrn`fgöa mgao`m cr`ffgba`rg` fba hbngagb F ∔ {∔h / f} y fbhbngagb F ∔ {` / f} os dguaîvbf`.
?- Vg
06
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
♣ Gafbrpbr`fgöa hom gacgagtb Vg so qugoroa gafbrpbr`r mbs fbnpmoebs ‖ h/f y `/f `m hbngagb y fbhbngagb rospoftgv`noato ho m`
w > `z + d pbhonbs gafbrpbr`r ua auovb omonoatb `m quo hoabnga`nbs fz + h gacgagtb, y mb sgndbmgz`nbs ∑, hocgagoahb m` cuafgöa c hom sgkugoato nbhb5
tr`ascbrn`fgöa
c F ∥ {∑} ↔ ↔ F ∥ {∑ } c ∔ h / f ↔ ↔ ∑ c ∑ ↔ ↔ `/f z 9 ≩ -h/f ↔ 9 + d)/(fz 9 + h) ≩ ` / f c ↔ (`z
♣ T`zöa hbdmo Vg z0 , z 4 y z6 sba tros puatbs hgstgatbs hom pm`ab z y
w0 , w4 y w6 sba tros puatbs hgstgatbs hom
0) > w 0 , c(z4) > w 4 y c(z6) > w 6 . pm`ab w, oatbafos t`m quo c(z ua` õagf` XMC w > c(z) @honàs hgfl` oxgsto tr`ascbrn`fgöa puoho bdtoaorso hospoe`ahb w ho m` cörnum`
(z - z 0 )(z 4 - z 6 ) (w - w 0 )(w 4 - w 6 ) , ` m` quo so hoabnga` r`zöa hbdmo. > (z - z 6 ))((z 4 - z 0 ) (w - w 6 )( )(w 4 - w 0 ) y
z0
v
z4
w0 z6
x
w6
w4 u
M` eustgcgf`fgöa ho m` cörnum` ho r`zöa hbdmo m` prbpbaonbs, fba fgort`s `yuh`s oa m` `ftgvgh`h sgkugoato.
∃ @ftgvgh`h ?5 Vo`
w > c ( z ) >
`z + d t`m quo c(z0) > w0 , c(z4) > w4 y c(z6) > w6 fz + h
`) Fbnprbd`r quo
c(z) - c(z0) >
(`h ∔ df)( z ∔ z 0 ) (fz + h )(fz 0 + h)
d) Xoagoahb oa fuoat` om rosumt`hb ho `) ,gahgf`r om rosumt`hb ho m`s sgkugoatos hgcoroafg`s c(z4) - c(z6) , c(z) - c(z6) y c(z4) - c(z0)
08
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
f) Fbnprbd`r quo
(c(z) - c(z 0 ))( )(c(z 4 ) - c(z 6 )) (z - z 0 )( )(z 4 - z 6 ) > y pbr mb (c(z) - c(z 6 ))( )(c(z 4 ) - c(z 0 )) (z - z 6 ))((z 4 - z 0 )
t`atb
w > c(z) vorgcgf`
m` r`zöa hbdmo gahgf`h` oa om oauafg`hb h) Y`r` honbstr`r quo os õagf` supbaor quo l`y btr` XMC w > k(z) t`m quo k(z0) > k(z4) > w4 y k(z6) > w6 , fbasghor`r m` tr`ascbrn`fgöa l(z) > k-0(c(z)) y eustgcgf`r eustgcgf `r quo5 h0) l(z) os ua` XMC h4) z0 , z4 y z6 sba tros puatbs cgebs ho l(z) , os hofgr l(z0) > z0 , l(z4) > z4 y l(z6) > z6
w0 ,
Fbafmusgöa5 Fbnb l(z) os ua` XMC quo tgoao tros puatbs cgebs oatbafos l(z) > z (²pbrquç2) , ho hbaho k-0(c(z)) > z y pbr mb t`atb c(z) > k(z) (²pbrquç2). Vo supusb quo l`dî` btr` XMC y so honbströ quo fbgafgho fba m` c(z) , pbr mb t`atb oxgsto ua` õagf` XMC quo oavî` tros puatbs hgstgatbs hom pm`ab z oa tros puatbs hgstgatbs hom pm`ab w y hgfl` XMC so l`mm` pm`ato`ahb m` r`zöa hbdmo y hospoe`ahb w.
Oeonpmbs
0- L`mm`r ua` XMC w > c(z) quo oavîo mbs puatbs z0> 9, z4> w0> -0, w4> 0 - 4g , w6> 9 rospoftgv`noato
4g , z6> 0 hom pm`ab z oa mbs puatbs
Toonpm`z`nbs mbs v`mbros h`hbs oa m` r`zöa hbdmo, oa osto f`sb toaonbs5
(z - 9)( )(4g - 0) (w + 0)( )(0 - 4g - 9) z ∔0 > y hospoe`ahb w (l`for om hospoeo) so bdtgoao w > (z - 0)( )(4g - 9) (w - 9))((0 - 4g + 0) gz + 0 4- L`mm`r ua` XMC w > c(z) quo oavîo mbs puatbs z0> 0, z4> w0> 9, z4> g , z6> ∑ rospoftgv`noato
g , z6> -0 hom pm`ab z oa mbs puatbs
Vo puoho utgmgz`r m` r`zöa hbdmo, fbnb ab so s`do bpor`r fba gacgagtb, so tbn` z6>
0/z* y
muokb so tbn` om mîngto p`r` z* toahgoahb ` forb5
gz * -0 (w - 9) )(- 0 + g ) w (gz * -0) + 0)g z 0 g ( ( ) ( z * ⇔ (z - 0)( ⇔ > > (z + 0) (g - 0) (wz * -0) (z + 0))((g - 0) wz * -0 z * (z - 0) w (-0) sg z* ↔ 9 oatbafos ost` õmtgn` oxprosgöa so fbavgorto oa , y hospoe`ahb w > (z + 0) (-0) z ∔0 quo vorgcgf` , fbnb os soafgmmb fbnprbd`r, m`s fbahgfgbaos pohgh`s. oafbatr`nbs5 w > z +0
0 (z - 0)( )(g + 0) z * > 0 (z + 0)( )(g - 0) w (g - 9 ) z * (w - 9) g -
6- L`mm`r ua` XMC
w > c(z) quo oavîo m` fgrfuacoroafg` | z | >0 oa m` roft` u > 9
0?
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Tofbrh`ahb quo m`s XMC tr`ascbrn`a m`s fgrfuacoroafg`s oa fgrfuacoroafg`s b roft`s, y rofbrh`ahb quo pbr tros puatbs ab `mgao`hbs p`s` ua` õagf` fgrfuacoroafg`, `mf`az` fba omokgr tros puatbs ho | z | > 0 , pbr oeonpmb mbs puatbs z0> 0, z4> g , z6> -0, y omokgr oa om pm`ab w tros puatbs ho m` roft` u > 9, pbr oeonpmb w0> 9 , z4> g , z6> ∑ , y so dusf` ua` XMC w > c(z) ho nbhb quo
c(zj) > wj p`r` j > 0,4,6 , fbnb os` tr`ascbrn`fgöa cuo l`mm`h` oa om oeonpmb z ∔0 `atorgbr, pbhonbs `sokur`r quo w > os ua` tr`ascbrn`fgöa tr`ascbrn`fg öa quo ro`mgz` mb quo so l` z +0 pohghb.
y
z4 > g
z ∔0 w> z +0
z6 > -0
v
z6> ∑ w4 > g
xx
ux
z0 > 0
w0 > 9
⊟ Bdsorv`fgöa5 Os soafgmmb vorgcgf`r quo mbs puatbs hom fîrfumb | z | ≨ 0 so tr`ascbrn`a oa mbs puatbs hom songpm`ab u ≨ 9 . @m omokgr mbs puatbs z0 , z4 y z6 ho m` fgrfuacoroafg` | z | >0 , mo lonbs `sgka`hb ua` brgoat`fgöa `atglbr`rg`: `m omokgr mbs puatbs w0 , w4 y w6 so m` roft` u > 9, mo lonbs `sgka`hb ua` brgoat`fgöa ho `d`eb l`fg` `rrgd` Yuoho `cgrn`rso quo m` gn`koa ho mbs puatbs quo ostàa ` m` gzqugorh` ho fgrfuacoroafg` |z | > 0 so tr`ascbrn`a oa puatbs quo ostàa ` m` gzqugorh` ho m` roft` u > 9 y puatbs quo ostàa ` m` horofl` ho m` fgrfuacoroafg` so tr`ascbrn`a oa puatbs quo ostàa ` m` horofl` ho m` roft` u > 9. v y z ∔0 w > z +0
x
u
•Oeorfgfgbs
z ∔ 4g m` gn`koa ho5 z+6 gω
gω /4
`) om soknoatb ho oxtronbs z9 > 6 o ω y z0> 4 o ω f) om softbr fgrfum`r |z ‖ 6| ≨ 8 , |@rk z | ≨ ω /6
d) m` roft` y > 4x -3 h) songpm`ab x 1 0
03
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
7- L`mm`r ua` tr`ascbrn`fgöa mgao`m cr`ffgba`rg` t`m quo5 `) z0 > 4g y z4 > 6 ‖ g so`a puatbs cgebs d) oavîo m` tora` (0, g, -4) oa m` tora` (9,-0, ∑) f) oavîo om songpm`ab x ≨ 9 oa om fîrfumb | w | ≨ 0 h) oavîo om fîrfumb | z ‖ g | ≨ 4 oa om songpm`ab To(w) ≯ Gn(w)
z∔g z+4 , X4 ( z ) > z ∔0 z ∔ 4g `) Vg m` gn`koa ho m` fgrfuacoroafg` | z ‖ 6 ‖ g j | > j pbr m` tr`ascbrn`fgöa tr`ascbrn`fgöa X0(z) os ua` roft` , ²quç pbsgdmos v`mbros puoho tbn`r m` fbast`ato j 2 d) L`mm`r m` tr`ascbrn`fgöa w >X4(X0(z)) , eustgcgf`r quo os ua` rbt`fgöa y hosfrgdgrm`. 09- H`h`s m`s tr`ascbrn`fgbaos
X0 ( z ) >
| z ‖ 4 | > | z + g | pbr X( z ) >
00- L`mm`r m` gn`koa ho mbs fbnpmoebs quo vorgcgf`a
g z - 4g z+g
y kr`cgf`r om fbaeuatb y su gn`koa. 04- L`mm`r m` gn`koa hom fbaeuatb @> {
z / | z - g | ≯ 0 y | z | ≨ 4 } pbr w >
8 z ∔ 4g
8. Xr`ascbrn`fgöa pbtoafg`5 w > za , a ∌A H`hbs
tr`ascbrn`fg öa w > za tbn` m` cbrn` z > r ogμ y w > π ogϟ , oatbafos m` tr`ascbrn`fgöa gϟ
a gaμ
π o > r o
π > r a ⇔ a ϟ > μ
Oeonpmbs5
0- L`mm`r m` gn`koa hom sokuahb fu`hr`ato pbr w > z
4
π > r 4 Vg w > z ⇔ 4 ϟ > μ 4
Fbnb mbs puatbs hom sokuahb fu`hr`ato vorgcgf`a ω /4 ≨ μ ≨ ω , r ≯ 9 ⇔ ω ≨ 4μ ≨ 4ω , r4 ≯ 9 ⇔ ω ≨ ϟ ≨ 4ω , π ≯ 9 , pbr mb t`atb m` gn`koa hom sokuahb fu`hr`ato os om songpm`ab gacorgbr v ≨ 9
y w>z4
v u
x
0;
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
4- L`mm`r ua` tr`ascbrn`fgöa quo oavîo | @rk(z) | ≨ ω /8 , | z | ≨ 4 oa om songpm`ab
u ≨ 9
y v
[>X(z)>2 4
x
u
M` tr`ascbrn`fgöa dusf`h` os m` fbnpbsgfgöa ho m`s tr`ascbrn`fgbaos quo so gahgf`a ` fbatgau`fgöa y quo y` cuorba ostuhg`h`s fba `atorgbrgh`h5 y
v
[>X(z)>2 4
X0(z) > z
x
u
X6 ( w * *) >
y*
y**
X4(w*) >w*/03 03
w ** ∔ 0 w ** + 0
x*
0
x**
z8 ∔0 z 8 ∔ 03 8 8 03 > 8 Ybr mb t`atb5 w > X(z) >X6(X4(X0(z)))> X6(X4(z )) > X6(z /03) > 8 z + 03 z +0 03
• Oeorfgfgbs 4
6
8
06- L`mm`r nohg`ato m`s tr`ascbrn`fgbaos X0(z) > z , X4(z) > z y X6(z) > z m` gn`koa ho5 `) m` songroft` y > x , y ≯ 9 f) om àakumb 9 ≨ @rk(z) ≨ ω /3
d) om fu`hr`ato x 1 9, y = 9 h) om softbr fgrfum`r | @rk(z)| ≨ ω /3 , | z | ≨ 4
08- Gahgf`r kràcgf`noato m`s tr`ascbrn`fgbaos sufosgv`s quo sucro om softbr ω //8 ≨ @rk(z) ≨ 6ω /8 4 pbr m` `pmgf`fgöa ho w > g z + 0 ‖ g
0<
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
0?- L`mm`r m` gn`koa hom trgàakumb ho vçrtgfos
z0 > -4 ‖ 4 g , z4 > -4 + 4g , z6 > 9 pbr w > g z4
03- L`mm`r ua` tr`ascbrn`fgöa quo oavîo om fbaeuatb fbaeuatb D > { w / | w + 0 | ≯ 0}
@ > {z / |z ‖ 4g| ≨ 0 , Gn(z) ≨ 4} oa om
?. Xr`ascbrn`fgbaos trgkbabnçtrgf`s o lgpordömgf`s @ nbhb ho oeonpmb so v` ` `a`mgz`r fba fgortb hot`mmo m` tr`ascbrn`fgöa w > soa z, m`s tr`ascbrn`fgbaos w > fbs z , w > sl z y w > fl z sba `aàmbk`s y prbpbaoa fbnb ua oeorfgfgb oeorfgfgb `m cga`m ho ost` soffgöa. Vg
u > soa x fl y w > soa z ⇔ u + gv > soa (x + gy) > soa x fly + g fbs x sly ⇔ v > fbs x sl y
Oeonpmbs5
0- L`mm`r, pbr w > soa z m` gn`koa ho mbs soknoatbs 5 `) M0 5 x > 9 , -0 ≨ y ≨ 0 f) M6 5 x > ω /4 , -0 ≨ y ≨ 4 o) M? 5 x > ω /8 , -4 ≨ y ≨ 0 `) Vg
d) M4 5 y > 9 , ω /4 ≨ x ≨ ω h) M8 5 y > 0 , ω /8 ≨ x ≨ ?ω /8
u > 9 u > soa 9 fl y ⇔ z ∌ M 0 5 x > 9 , -0 ≨ y ≨ 0 y w > soa z ⇔ v > sl y v > fbs 9 sl y
Fbnb sl y os ostrgft`noato frofgoato s`donbs quo5 sg -0 ≨ y ≨ 0 ⇔ sl(-0) ≨ sl y ≨ sl 0 ⇔ - sl0 ≨ v ≨ sl 0
Ybr mb t`atb m` gn`koa ho
M0 sba
u > 9 mbs fbnpmoebs w > u + gv quo vorgcgf`a5 ∔ sl 0 ≨ v ≨ sl 0 v
y
w>soa z
0 -0
d) Vg
sl0
x
u
-sl 0
u > soax u > soa x fl 9 ⇔ z ∌ M 4 5 y > 9 , ω /4 ≨ x ≨ ω y w > soa z ⇔ v > 9 v > fbs x sl 9
07
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Fbnb soa x os ostrgft`noato hofrofgoato sg ω /4 ≨ x ≨ ω , s`donbs quo5 sg ω /4 ≨ x ≨ ω ⇔
soa ω /4 ≯ soa x ≯ soa ω ⇔ 0 ≯ u ≯ 9
9 ≨ u ≨ 0 Ybr mb t`atb m` gn`koa ho M4 sba mbs fbnpmoebs w > u + gv quo vorgcgf`a5 v > 9 v
y
w>soa z u > fl y u > soa( ω / 4) fl y f) Vg z ∌ M 6 5 x > ω /4 , -0 ≨ y ≨ 4 y w > soa z ⇔ ⇔ 9 0ω /4) slu y ω /4 v > 9 v > fbs( x
Fbnb fl y hofrofo sg -0 ≨ y ≨ 9 y frofo sg 9 ≨ y ≨ 4 , p`r` oafbatr`r su v`rg`fgöa dusf`nbs su nàxgnb y su nîagnb `dsbmutb oa om gatorv`mb forr`hb Z-0, 4^ , quo so prbhufoa oa y > 4 y oa y > 9 rospoftgv`noato ⇔ fl 9 ≨ fl y ≨ fl 4 ⇔ 0 ≨ u ≨ fl 4 Ybr mb t`atb m` gn`koa ho y
0 ≨ u ≨ fl 4 M6 sba mbs fbnpmoebs w > u + gv quo vorgcgf`a5 v > 9
4 -0
w>soa z ω /4
x
v
0
fl4
u
u
u > soax fl 0 fl0 > soax ⇔ h) Vg z ∌ M8 5 y > 0 , ω /8 ≨ x ≨ ?ω /8 y w > soa z ⇔ v v > fbs x sl 0 > fbs x sl0
omov`ahb `m fu`hr`hb ost`s õmtgn`s oxprosgbaos y sun`ahb ngondrb ` ngondrb so mbkr` omgnga`r
u4 v4 m` v`rg`dmo x bdtoagoahb + > 0 , quo roprosoat` ua` omgpso. Os gnpbrt`ato bdsorv`r fl 4 0 sl 4 0 quo oa om r`zba`ngoatb `atorgbr ab so l` utgmgz`hb om h`tb ω /8 ≨ x ≨ ?ω /8 , fbnb osto gatorv`mb tgoao `npmgtuh ω, so hosproaho quo m` gn`koa sorà sömb ua trbzb ho m` omgpso gahgf`h`.. Y`r` oafbatr`r oso trbzb so dusf` om puatb gagfg`m ho furv` gn`koa, om puatb cga`m y sg os aofos`rgb m` gn`koa ho `mkõa btrb puatb hom soknoatb h`hb fbnb so nuostr` ` fbatgau`fgöa5
Vg
Vg
z > (ω /8 , 0)
z > (?ω /8 ,0)
⇔ u > soa( ω / 8) fl 0 > v > fbs (ω /8) sl 0 >
4 4 4 fl0 ⇔ sl0 w > fl0, 4 4 4 4 sl0 4
4 ⇔ u > soa(?ω / 8) fl 0 > ∔ 4 fl0 v > fbs (?ω /8) sl 0 > ∔ 4 sl0 4
⇔ w > ∔ 4 fl0,∔ 4 sl0 4 4
49
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Vg
z > (ω , 0) ⇔ u > soaω fl 0 > 9
v > fbs ω sl 0 > ∔sl0
⇔ w > (9, ∔ ∔sl0)
y v
w>soa z
v
4 4 sl0 fl0, 4 4
0 ω /8
o) Vg
ω
?ω /8
x
u
(9,- sl0)
z ∌ M ? 5 x > ω /8 , -4 ≨ y ≨ 0 y w > soa z 4 ⇔ 4 ∔ fl0,∔ sl0 4 4
u > soa ( ω / 8) fl y ⇔ v > fbs ( ω /8) sl y
u soa( ω / 8) > fly v > sly fbs(ω /8)
Fbnb soa (ω /8) > fbs ( ω /8) > 4 / 4 y rofbrh`ahb quo fl4 y - sl4 y > 0 , so puoho omgnga`r m` v`rg`dmo y omov`ahb `m fu`hr`hb ost`s õmtgn`s oxprosgbaos y rostàahbm`s ngondrb ` ngondrb
u4 v4 bdtoagoahb ∔ > 0 , quo roprosoat` ua` lgpçrdbm`. Fbnb oa om r`zba`ngoatb `atorgbr ab 0 / 4 0 / 4 so l` utgmgz`hb om h`tb -4 ≨ y ≨ 0 , so hosproaho quo m` gn`koa sorà sömb ua trbzb ho m` lgpçrdbm` y p`r` oafbatr`rmb so dusf` om puatb gagfg`m ho furv` gn`koa, om puatb cga`m y sg os aofos`rgb m` gn`koa ho `mkõa btrb puatb hom soknoatb h`hb fbnb so nuostr` ` fbatgau`fgöa5
Vg
Vg
Vg
z > (ω /8 , -4 )
z > (ω /8 , 0 )
u > soa ( ω / 8) fl (-4) > ⇔ v > fbs ( ω /8) sl (-4) > ∔
u > soa ( ω / 8) fl0 > ⇔ v > fbs ( ω /8) sl 0 >
4 fl0 4 4 sl0 4
z > (ω /8 , 9 ) ⇔ u > soa (ω / 8) fl 9 >
4 fl4 4 4 sl4 4
v > fbs ( ω /8) sl 9 > 9
4 4
⇔ w > 4 fl4,∔ 4 sl 4 4 4
⇔ w > 4 fl0, 4 sl0 4 4 ⇔ w > 4 ,9 4
y
w>soa z
0 ω /8
4 4 4 fl0, 4 sl0
v
x
u
-4 4 ,9 4
4 4 ∔ 4 fl4, 4 sl 4
40
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
• Oeorfgfgbs 0;- L`mm`r pbr
w > soa z m` gn`koa ho5 gω
`) om soknoatb ho oxtronbs z9 > 9 y z0> 4 o ω f) om roftàakumb 9 ≨ x ≨ ω /4 , 9 ≨ y ≨ 0 0 4 , 9 ≨ x ≨ ω /3 h) m` cr`ae` 9 = x = ω /4 , y = 9
D os m` gn`koa hom fbaeuatb @ pbr w > soa z
@ > {(x,y) / | x | = ω /4, y 1 9} , D > {(x, y) / y 1 9} @ > {(x,y) / | x | = ω /4} , D > F - {(x, y) / y > 9 , | x | ≯ 0 } @ > {(x,y) / | x | ≨ ω /4} , D>F
07- `) Eustgcgf`r quo fbs z > soa (z + ω /4) y hohufgr quo m` tr`ascbrn`fgöa w > fbs z os m` fbnpbsgfgöa ho m` tr`ascbrn`fgöa w > soa z profohgh` ho ua` tr`sm`fgöa ` m` horofl` ho ω /4 uagh`hos. d) Eustgcgf`r quo sl z > -g soa(gz) , fl z > soa(gz + ω /4), y hosfrgdgrm`s fbnb fbnpbsgfgöa oatro m` tr`ascbrn`fgöa w > soa z y btr`s quo hodo gahgf`r.
3. Xr`ascbrn`fgöa oxpbaoafg`m y mbk`rgtnb Y`r` `a`mgz`r m` tr`ascbrn`fgöa oxpbaoafg`m so fbasghor` w oa cbrn` oxpbaoafg`m, os hofgr π ogϟ , y z oa cbrn` dgaöngf`, os hofgr z > x + gy , oatbafos5 z
gϟ
w > o ⇔ π o > o
x +gy
x gy
> o o
w>
π > o x hbaho j os ua aõnorb oatorb ⇔ ϟ > y + 4 j ω
Y`r` `a`mgz`r m` tr`ascbrn`fgöa mbk`rgtnb so fbasghor` w oa cbrn` dgaöngf`, os hofgr u + gv , y z oa cbrn` oxpbaoafg`m, os hofgr z > r ogμ , oatbafos5
w>
u > ma r w > Ma z ⇔ u + gv > ma r + g μ ⇔ v > μ Oeonpmbs5
0- L`mm`r pbr
w > oz m` gn`koa ho m` roft` y > 9, `a`mgz`ahb su gn`koa sg x ≯ 9 b sg x ≨ 9
π > o x , oatbafos m` gn`koa ho m` roft` y > 9 os V`donbs quo sg w > o ⇔ ϟ > y + 4 j ω z
π > o x ϟ > 4 j ω
44
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Fbnb ϟ > 4j ω , mbs fbnpmoebs w tgoaoa `rkunoatb fbnpmoebs w so oafuoatr`a oa om oeo ro`m pbsgtgvb.
9 , 4 ω , -4ω, 8 ω ,…. y pbr mb t`atb tbhbs mbs
sg x ≯ 9 ⇔ o x ≯ o 9 ⇔ π ≯ 0 Fbnb o os frofgoato ⇔ sg x ≨ 9 ⇔ o x ≨ o 9 ⇔ π ≨ 0 x
Oatbafos so puoho `cgrn`r quo5 M` gn`koa ho m` songroft` y > 9 , fba x ≯ 9 sba mbs fbnpmoebs hom oeo ro`m pbsgtgvb quo tgoaoa nöhumb n`ybr b gku`m ` 0, os hofgr su gn`koa os m` songroft` v > 9 fba u ≯ 0 M` gn`koa ho m` songroft` y > 9 , fba x ≨ 9 sba mbs fbnpmoebs hom oeo ro`m pbsgtgvb quo tgoaoa nöhumb noabr b gku`m ` 0, os hofgr su gn`koa os om soknoatb v > 9 fba 9 ≨ u ≨ 0 Ybr mb t`atb m` gn`koa ho m` roft` y > 9 os m` songroft` v > 9 fba u ≯ 9 y
9
v
y
u
x
9
y
v
x
9 0
9 0 Gn`koa ho y > 9 fba x ≯ 9
v
Gn`koa ho y > 9 fba x ≨ 9
9
u
x
9 0
u
Gn`koa ho m` roft` y > 9
y
4- L`mm`r m` gn`koa ho m` zba` sbndro`h` pbr
w > Ma z
4
M` rokgöa sbndro`h` puoho hosfrgdgrso fbnb | z | ≯ 4, -ω /4 ≨ @rk(z) ≨ ω /4 , os hofgr r ≯ 4 , -ω /4 ≨ μ ≨ ω /4
x
u > ma r oatbafos u + g v > Ma (r og μ) ⇔ v > μ fbnb r ≯ 4 ⇔ ma r ≯ ma 4 , y pbr mb t`atb u ≯ ma 4
Vo s`do quo
fbnb -ω /4 ≨ μ ≨ ω /4 y v > μ ⇔ -ω /4 ≨ v ≨ ω /4 pbr mb t`atb m` gn`koa ho zba` sbndro`h` os m` cr`ae` song gacgagt` hocgagh` pbr u ≯ ma 4 y -ω /4 ≨ v ≨ ω /4
v
ω /4 u
Ma 4
-ω /4
• Oeorfgfgbs 49- L`mm`r pbr
w > oz m` gn`koa ho5
`) om roftàakumb 40- L`mm`r pbr
-0 ≨ x ≨ 6 , 9 ≨ y ≨ ω /8
w > Ma z m` gn`koa ho5
d) m` cr`ae` x 1 9 , 9 = y = ω
46
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
`) m` fbrba` f) om àakumb
4 ≨ | z | ≨ 8 - ω = @rk(z) = ω /4
d) om fîrfumb `dgortb | z | = 6 h) om softbr |z | = 4 , |@rk(z)|= ω /8
;. Xr`ascbrn`fgöa fbacbrno ♣ _a `rfb F0 oa om pm`ab os fu`mqugor fbaeuatb ho puatbs quo puoho hosfrgdgrso pbr m` ofu`fgöa x > x(t ) p`r`nçtrgf` , fba t p`rànotrb ro`m portoaofgoato ` ua gatorv`mb G , hbaho x(t) o y(t) y > y( t ) sba cuafgbaos fbatgau`s oa G. Oa om pm`ab fbnpmoeb mbs puatbs hom `rfb z(t) > x(t) + g y(t) , fba t ∌ G .
F0 sba mbs fbnpmoebs
♣ Vo hgfo quo ua `rfb F0 ho ofu`fgöa z(t) os su`vo sg m` cuafgöa z‗(t) > x‗(t) + g y‗(t) ab so `aum` y os fbatgau` p`r` t ∌ G . ♣ Vo hgfo quo ua `rfb os su`vo pbr tr`nbs b su`vo pbr p`rtos (spp) sg fbasgsto oa ua aõnorb cgagtb ho `rfbs su`vos uaghbs pbr sus oxtronbs. Vg F 0 os spp oatbafos m`s cuafgbaos x(t) o y(t) sba fbatgau`s porb sus horgv`h`s sba soffgba`mnoato fbatgau`s.
♣ _a `rfb F0 os sgnpmo sg ab so fbrt` ` sî ngsnb, os hofgr sg z(t0) > z(t4) ⇘ t0 > t4 ♣ _a `rfb os forr`hb sg om puatb gagfg`m fbgafgho fba om puatb cga`m. Vg ua` furv` os sgnpmo y forr`h` so hoabnga` furv` ho Ebrhàa.
y
y
x
@rfb sgnpmo y su`vo
y
x
@rfb sgnpmo y su`vo spp
x
Furv` ho Ebrhàa
♣ Tbt`fgöa ho t`akoatos F0 ua` furv` su`vo ho ofu`fgöa z(t), fba t∌ G y so` F0* su gn`koa pbr m` tr`ascbrn`fgöa w > c(z) oatbafos F0* tgoao ofu`fgöa p`rànotrgf` w(t) > c(z(t)), fba t ∌ G . Vo`
F0 p`s` pbr om puatb ho fbbrhoa`h`s (x9, y9) oatbafos oxgsto ua aõnorb ro`m t9 ∌ G t`m quo z(t9) > x(t9) + g y(t9) > x9 + g y9 > z9 y F0* p`s` pbr w9 > c(z9)> u9 + g v9
Vg
48
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Fbnb F0 os su`vo `hngto voftbr t`akoato ab aumb y fbatgaub oa f`h` uab ho sus puatbs, oa p`rtgfum`r oa om puatb ho fbbrhoa`h`s ( (xx9, y 9) , su voftbr t`akoato tgoao fbnpbaoatos (x‗(t9), y‗(t9)) , pbr mb t`atb z‗(t9) > x‗(t9)+ g y‗(t9) os ua fbnpmoeb fuyb `rkunoatb h` m` gafmga`fgöa hom voftbr t`akoato oa z9 y mb gahgf`nbs ΰ > `rk(z‗(t9)). So`nbs quo sg c(z) os `a`mîtgf` oa z 9 y c‗(z9) ≩ 9 oatbafos m` furv` ab aumb oa w9 fuy` gafmga`fgöa ostà h`h` pbr δ > `rk(w‗(t9))5
F0
y
w>c(z)
F0* `hngto voftbr t`akoato
v
δ
v9
ΰ
F 0 *
y9 x9 horgv`ahb
u9
x
u
w (t) > c(z(t)) pbr rokm` ho m` f`hoa` y ov`mu`ahb oa t9 bdtoaonbs5 w‗(t9) > c‗(z(t9)). z‗(t9) > c‗(z9). z‗(t9)
Fbnb c‗(z9) ≩ 9, pbr mb supuostb, y z‗(t9) ≩ 9 , pbr sor F0 su`vo, oatbafos soatghb tbn`r `rkunoatb ` `ndbs ngondrbs bdtoagoahb5
w‗(t9) ≩ 9 y tgoao
`rk(w‗(t9)) > `rk(c‗(z9)) + `rk(z‗(t9)) quo os oqugv`moato ` `cgrn`r quo5
δ > `rk(c‗(z9)) + ΰ
Ybr mb t`atb om àakumb ho gafmga`fgöa ho m` t`akoato ` m` furv` F0* , tr`z`h` oa w9 > c(z9) , hgcgoro hom àakumb ho gafmga`fgöa ho m` t`akoato ` m` furv` F0 ,tr`z`h` oa z9 , oa om àakumb ζ ζ9 > `rk(c‗(z9)), `m quo suomo hoabnga`rso àakumb ho rbt`fgöa ho m` t`akoato.
Oeonpmbs5 0- H`h` c(z) > 0/z , l`mm`r om àakumb quo kgr`a m`s t`akoatos ` m`s furv`s quo p`s`a pbr 0 + g, os hofgr sg ΰ os om àakumb ho gafmga`fgöa ho ua` furv` oa om puatb z9 > 0 + g, l`mm`r om àakumb ho gafmga`fgöa ho su gn`koa oa om puatb c(0 + g) Fbnb
c‗(z) > -0/z4 oatbafos
F
y
`rk(c‗(z)) >`rk(-0/z4) > `rk(-0) ‖`rk(z4) > ω - 4 `rk z , pbr mb t`atb sg ΰ os om àakumb ho gafmga`fgöa ho ua` furv` oa om puatb z9 > 0 + g y δ os om àakumb ho gafmga`fgöa ho su gn`koa oa om puatb w9 > c(0 + g) > ¾ - g ¾ , s`donbs quo5
δ > `rk(c‗(0 + g)) + ΰ > ω - 4 `rk(0+g) + ΰ > ω - 4 ω /8 + ΰ > ω /4 + ΰ
ΰ 0 0
x
4?
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Fbnb δ > ¾ ω + ΰ , pbhonbs `cgrn`r quo om àakumb quo kgr`a m`s t`akoatos ` fu`mqugor furv` quo p`so pbr 0 + g os ω /4 4- Xoagoahb oa fuoat` m` rospuost` hom oeorfgfgb `atorgbr, l`mm`r sga l`for fuoat`s m` gn`koa ho m` roft` y > x pbr c(z) > 0/z Fbnb m` roft` y > x p`s` pbr om brgkoa, su gn`koa pbr c(z) > 0/z os ua` roft` quo p`s` pbr om brgkoa hom pm`ab w, fbnb `honàs p`s` pbr om puatb 0 + g , s`donbs pbr om oeonpmb `atorgbr quo sus t`akoatos kgr`a ua àakumb gku`m ` ω /4 . Fbnb om àakumb ho gafmga`fgöa ho m` roft` y > x os gku`m ` ω /8 , om àakumb ho gafmga`fgöa ho su gn`koa os ω /4 + ω /8 > 6ω /8 , pbr mb t`atb su gn`koa os m` roft` v > tk(6ω /8) u , b v > -u
♣ Fbasorv`fgöa ho àakumbs Vo`a F0 y F4 hbs furv`s su`vos quo p`s`a pbr z9 y so`a ΰ0 y ΰ4 mbs àakumbs ho gafmga`fgöa ho sus rospoftgv`s t`akoatos tr`z`h`s oa z9 oatbafos s`donbs quo 5
δ0 > `rk(c‗(z9)) + ΰ0 δ4 > `rk(c‗(z9)) + ΰ4 hbaho δ0 y δ4 sba mbs àakumbs ho gafmga`fgöa ho m`s t`akoatos tr`z`h`s oa w9 > c(z9) ho m`s furv`s F0* y F4* , gnàkoaos ho F0 y F4 rospoftgv`noato, sgonpro quo c(z) so` `a`mîtgf` y c‗(z9) ≩ 9. Tost`ahb ngondrb ` ngondrb m`s oxprosgbaos `atorgbros so bdtgoao5
δ0 - δ4 > ΰ0 - ΰ4
Ybr mb t`atb om àakumb δ 0 - δ4 , nohghb hosho F4* l`st` F 0* , os om ngsnb oa n`kagtuh y soatghb quo om àakumb ΰ0 - ΰ4 , nohghb hosho F4 l`st` F0.
y
F0
w>c(z)
δ0 - δ4 v
ΰ0 - ΰ4
F0*
F4*
F4 x
u
♣ Xr`ascbrn`fgöa fbacbrno Vo`a F0 y F4 hbs furv`s fu`mosqugor` fu`mosqugor` , su`vos y brgoat`h`s hom pm`ab z quo so fbrt`a oa z9 y so`a F0* y F4* sus rospoftgv`s gnàkoaos pbr w > c(z) , so hgfo quo ost` tr`ascbrn`fgöa os fbacbrno oa z9 sg fbasorv` om t`n`ðb y m` brgoat`fgöa ho mbs àakumbs, os hofgr5 om àakumb oatro F0 y F4 fbgafgho oa n`kagtuh y soatghb fba om àakumb oatro F0* y F4* .
43
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
∃ @ftgvgh`h 35 Eustgcgf`r om sgkugoato oauafg`hb5 fbacbrno oa z9
sg
c(z) os `a`mîtgf` oa z9 y c‗(z9) ≩ 9 oatbafos c(z) os
Oeonpmbs5
0- M` tr`ascbrn`fgöa p`r` tbhb z .
w > oz os `a`mîtgf` y su horgv`h` auaf` so `aum`, pbr mb t`atb os fbacbrno
`aum` sömb oa z > 9, pbr mb 4- M` tr`ascbrn`fg tr`ascbrn`fgöa öa w > z4 os `a`mîtgf` y su horgv`h` c‗(z) > 4z so `aum` t`atb os fbacbrno p`r` tbhb z ≩ 9. ²Yuoho sor fbacbrno oa z > 92, m` rospuost` os ganohg`t` puos sg so fbasghor`a hbs roft`s quo p`soa pbr om brgkoa fuybs àakumbs ho gafmga`fgöa sba μ0 y μ4, sus gnàkoaos sba hbs roft`s quo t`ndgça p`s`a pbr om brgkoa y fuybs àakumbs ho gafmga`fgöa sba 4μ0 y 4μ4 , pbr mb t`atb om àakumb oatro m`s furv`s gnàkoaos os om hbdmo hom v y àakumb oatro m`s furv`s h`h`s. μ4>6ω /8 4
w> z
4μ4>6ω / 4
μ0>ω /8
4 μ0>ω /4 u
x
• Oeorfgfgbs 44- L`mm`r om àakumb quo kgr`a m`s t`akoatos ` m`s furv`s quo p`s`a pbr tr`ascbrn`h`s pbr w > c(z) `) c(z) > 6z4 ‖ 4z , z9 > g/6
d) c(z) > oz , z9 > ωg
f)
z9 fu`ahb sba
z 0
c ( z ) > z 4 ++ 6 , z9 > 0
46- H`h` m` tr`ascbrn`fgöa c(z) > z4 `) Honbstr`r quo w > c(z) f`ndg` m`s hgroffgbaos ho m`s furv`s quo p`s`a pbr z9 > 4 + g oa om àakumb δ > `rf tk ¾ d) L`mm`r m` gn`koa ho m`s roft`s y > 0 , x > 4 , y > ¾ x pbr w > c(z) y fbnprbd`r mb honbstr`hb oa `)
w > za , a ∌ A , f`ndg` m`s hgroffgbaos oa om puatb z9 > r9 o g μ9 oa om àakumb δ > (a ‖ 0)μ9
48-Honbstr`r quo m` tr`ascbrn`fgöa
4?- Gahgf`r höaho sba fbacbrnos m`s sgkugoatos tr`ascbrn`fgbaos5
4;
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
6
`) w > 0 ‖ fbs z
d) w > z
‖ 6z
f) w > 4/z
h) w > o
4z
43- H`h` k(z) > 6 fbs z - g soa z , oxpros`rm` oa cuafgöa ho oxpbaoafg`mos fbnpmoebs y `vorgku`r p`r` quç v`mbros ho z os fbacbrno. 4;- H`hbs mbs fbaeuatbs
@ > { z > r ogμ / -ω /8 ≨ μ ≨ ω /8 , r ≯ 4 } , D > { w > π og ϟ / π ≯ 4 }
`) L`mm`r ua` cuafgöa quo tr`ascbrno @ oa D ho nbhb quo z9 > 4 ogω /8 so` puatb cgeb . d) Fbnprbd`r quo m` tr`ascbrn`fgöa l`mm`h` oa `) os fbacbrno oa om puatb z0 > 4 o gahgf`r quç àakumb kgr`a m`s t`akoatos oa hgflb puatb. Nbstr`r kràcgf`noato mb quo `cgrn` fbasghor`ahb m` fgrfuacoroafg` r > 4 y m` songroft` μ > 9 y sus gnàkoaos muokb ho `pmgf`h` `pmgf`h` m` cuafgöa.
•• •• Oeorfgfgbs `hgfgba`mos 4 {z / 9 = @rk z = ω /8 , 4 = | z | = ∑ }
`) L`mm`r su gn`koa nohg`ato m` tr`ascbrn`fgöa d) L`mm`r ua` tr`ascbrn`fgöa quo oavîo m` rokgöa
w > 4g Ma z. Kr`cgf`r @ oa D > { w / To(w) 1 4 Gn(w)}
69- Vg T os m` rokgöa mgngt`h` pbr m`s fgrfuacoroafg`s pbr m` tr`ascbrn`fgöa w > 0 / (z - g)
|z| > 0 y |z +0/4 g | > 6/4 , l`mm`r su gn`koa
u(x,y) + g v(x,y) os `a`mîtgf` oa ua fbaeuatb H , s`donbs quo u(x,y) y v(x,y)
sba `rnöagf`s oa H y pbr mb t`atb vorgcgf`a m`s
∄ 4u ∄ 4u + > 9 , ∄x 4 ∄y 4
ofu`fgöa hgcoroafg`m ho M`pm`fo5
∄4v ∄4v + > 9 ∄x 4 ∄y 4
, p`r` (x,y) ∌H
pbr ommb so puohoa oafbatr`r nbatbaos ho sbmufgbaos ho m` ofu`fgöa hgcoroafg`m ho M`pm`fo oa fbasghor`ahb m` p`rto ro`m b gn`kga`rg` ho ua cuafgöa `a`mîtgf` oa H.
H
4<
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Ybr oeonpmb
To(z4) > x4 - y 4 , Gn(soa z) > fbs x sl y , To(o6z) > o6x fbs (6y) sba `rnöagf`s oa
tbhb om pm`ab fbnpmoeb pbr sor m`s fbnpbaoatos ro`mos b gn`kga`rg`s ho cuafgbaos `a`mîtgf`s y pbr ommb sba sbmufgbaos ho m` ofu`fgöa hgcoroafg`m ho M`pm`fo. ² Fönb oafbatr`r sbmufgbaos ho m` ofu`fgöa ho M`pm`fo oa ua hbngagb H quo vorgcgquo fgort`s fbahgfgbaos fbast`atos sbdro m` crbator` ho H ` m`s quo so hoabnga`a fbahgfgbaos ho fbatbrab2 Soronbs ` fbatgau`fgöa quo sg om rofgatb
H os ua àakumb fba vçrtgfo oa om brgkoa b os ua` fbrba`
fgrfum`r t`ndgça foatr`h` oa om brgkoa ho fbbrhoa`h`s b os ua` cr`ae` lbrgzbat`m b vortgf`m , os nuy soafgmmb oafbatr`r m` sbmufgöa.
♣ F`sb G5 Om hbngagb H os ua àakumb fba vçrtgfo oa om brgkoa quo ab
fbatgoao `m oeo ro`m aok`tgvb
Puoronbs oafbatr`r ua` cuafgöa quo so` sbmufgöa ho m` ofu`fgöa ho M`pm`fo oa om rofgatb
y
gμ
H > {z / z > r o , r 1 9 , μ9 = μ = μ0 fba μ9 1 - ω}
y m`s fbahgfgbaos ho fbatbrab so h`a sbdro m`s songroft`s μ > μ9 y μ > μ0 . M` cuafgöa `rnöagf` quo l`y quo oafbatr`r oa osto f`sb hopoahorà sömb ho μ.
μ 9
μ 0 x
Vo prbpbao ua` cuafgöa ho m` cbrn` S(r, μ) > @ μ + D , quo ovghoatonoato os `rnöagf` pbr sor m` fbnpbaoato gn`kga`rg` ho m` cuafgöa `a`mîtgf` @ Ma z + D g , y so hotornga`a m`s fbast`atos ro`mos @ y D ho nbhb quo vorgcgquoa m`s fbahgfgbaos ho fbatbrab ost`dmofgh`s oa om oeorfgfgb.
Oeonpmb5
y
L`mm`r ua` cuafgöa `rnöagf` S(x,y) hocgagh` oa
H > {z > r ogμ / r 1 9 , - ω /4 = μ = 6ω /8} t`m quo S(x,y ) > -; sbdro m` songroft` μ > 6ω /8
S > -; S> -6
x
S(x,y ) > 6 sbdro m` songroft` μ > -ω /4 Vo prbpbao S > @ μ + D y so hotornga`a m`s fbast`atos Vg μ > 6ω /8 oatbafos
@ y D r`zba`ahb hom sgkugoato nbhb5
- ; > @ 6ω /8 + D , sg μ > -ω /4 oatbafos 6 > @ (- ω /4) + D
Tost`ahb ost`s hbs ofu`fgbaos so bdtgoao - 09 > ?ω /8 @
, hospoe`ahb so bdtgoao quo @ > - -0 47
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
Ybr mb t`atb S > - ∔ < ω Z`rftk (y x ) + ω^ ∔ 0 sg x = 9 , y 1 x - ? sg x > 9 , y 1 9 p`r` ommb so l` toaghb oa fuoat` quo5
sg
(x,y) portoaofo ` H y ostà oa om prgnor b fu`rtb fu`hr`ato oatbafos -ω /4 = μ = ω /4 , pbr
mb t`atb μ > `rftk(y/x)
sg
(x,y) portoaofo ` H y ostà oa om sokuahb fu`hr`ato oatbafos ω /4 = μ = 6ω /8 , pbr mb t`atb
μ > `rftk(y/x) + ω
sg (x,y) portoaofo `m oeo gn`kga`rgb pbsgtgvb oatbafos μ > ω /4
Vo hoe` fbnb oeorfgfgb m` vorgcgf`fgöa quo
S(x,y) os `rnöagf` oa H y s`tgsc`fo m`s fbahgfgbaos ho
fbatbrab pohgh`s.
♣ F`sb GG5
Om hbngagb H os ua` fbrba` fgrfum`r
Puoronbs oafbatr`r ua` cuafgöa quo so` sbmufgöa ho m` ofu`fgöa ho M`pm`fo oa m` fbrba` fgrfum`r foatr`h` oa om brgkoa H > {z / z > r ogμ, r9 = r = r0 } y m`s fbahgfgbaos ho fbatbrab so h`a sbdro m`s fgrfuacoroafg`s r > r9 y r > r0 .
y
r>r
x
r > r9 M` cuafgöa `rnöagf` quo l`y quo oafbatr`r oa osto f`sb hopoahorà sömb ho r. Yrbpbaonbs ua` cuafgöa ho m` cbrn` S(r, μ) > @ ma r + D , quo ovghoatonoato os `rnöagf` pbr sor m` fbnpbaoato ro`m ho m` cuafgöa @ Ma z + D , quo sg dgoa ab os `a`mîtgf` oa om oeo ro`m aok`tgvb, su fbnpbaoato ro`m os fbatgau` y horgv`dmo s`mvb oa z > 9, y hotornga`nbs m`s fbast`atos ro`mos @ y D ho nbhb quo vorgcgquoa m`s fbahgfgbaos ho fbatbrab ost`dmofgh`s oa om oeorfgfgb.
Oeonpmb5
L`mm`r ua` cuafgöa `rnöagf` S(x,y) hocgagh` oa H > {z > r ogμ / , 6 = r = 3} 3} t`m quo
y
S> -4
S(x,y ) > 8 sbdro m` fgrfuacoroafg` r > 6
S> 8
x
69
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
S(x,y ) > -4 sbdro m` fgrfuacoroafg` r > 3 Vo prbpbao S > @ mar + D y so hotornga`a @ y D r`zba`ahb hom sgkugoato nbhb5 Vg > 6 oatbafos Vg rr > 3 oatbafos
8 >>@@mama63++DD -4
Tosbmvgoahb ost`s hbs ofu`fgbaos so oafuoatr` quo
@>
3 ma 6 ∔ ma 3
>
3 3 ma 6 , D > 8 ∔ . ma 0 4 ma 0 4
3 3 ma 6 +8∔ , quo oxpros`h` oa cuafgöa ho x, y rosumt` sor5 ma r ma 0 4 ma 0 4 3 3 ma 6 S( x, y ) > 0 ma x 4 + y 4 + 8 ∔ 0 ma 4 ma 4
Ybr mb t`atb
S >
Vo hoe` fbnb oeorfgfgb m` vorgcgf`fgöa ho quo ho fbatbrab pohgh`s.
S(x,y) os `rnöagf` oa H y s`tgsc`fo m`s fbahgfgbaos
♣ F`sb GGG5 Om hbngagb H os ua` cr`ae` lbrgzbat`m b vortgf`m gacgagt` y
`) Puoronbs oafbatr`r ua` sbmufgöa ho m` ofu`fgöa ho M`pm`fo oa m` cr`ae` lbrgzbat`m gacgagt` H > {(x,y) / - ∑ = x = ∑ , ` = y = d } y m`s fbahgfgbaos ho fbatbrab so h`a sbdro m`s roft`s y > ` y y > d . M` cuafgöa `rnöagf` quo l`y quo oafbatr`r oaosto f`sb hopoahorà sömb ho y.
y>d y>`
x
Vo prbpbao ua` cuafgöa ho m` cbrn` S(x, y) > @ y + D , quo ovghoatonoato os `rnöagf` pbr sor m` fbnpbaoato gn`kga`rg` ho m` cuafgöa `a`mîtgf` @ z + D g , y so hotornga`a m`s fbast`atos ro`mos @ y D ho nbhb quo vorgcgquoa m`s fbahgfgbaos ho fbatbrab ost`dmofgh`s oa om oeorfgfgb. y
f) Vg H > {(x,y) / ` = x = d , - ∑ = y = ∑ } os ua` cr`ae` vortgf`m gacgagt` y m`s fbahgfgbaos ho fbatbrab so h`a sbdro m`s roft`s x > ` y x > d , m` cuafgöa `rnöagf` quo l`y quo oafbatr`r oa osto f`sb hopoahorà sömb ho x.
x>d
x>` x
Vo prbpbao ua` cuafgöa ho m` cbrn` S(x, y) > @ x + D , quo ovghoatonoato os `rnöagf` pbr sor m` fbnpbaoato ro`m ho m` cuafgöa `a`mîtgf` @ z + D , y so hotornga`a m`s fbast`atos ro`mos @ y D ho nbhb quo vorgcgquoa m`s fbahgfgbaos ho fbatbrab ost`dmofgh`s oa om oeorfgfgb. Oeonpmb
y
8
L`mm`r ua` cuafgöa c(x,y) quo s`tgc`k` m` ofu`fgöa ho M`pm`fo oa om fbaeuatb H > {(x,y) / - ∑ = x = ∑ , -4 = y = 8 } y
x
60
-4Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
vorgcgquo
c(x, 8) > -6 , c(x,-4) > 7
M` cuafgöa `rnöagf` quo l`y quo oafbatr`r oa osto f`sb hopoahorà sömb ho y, prbpbaonbs c(x,y) > @y + D y m` ov`mu`nbs sbdro m` crbator` ho H5
c ( x,8) > @8 + D > ∔6 c ( x , ∔ 4 ) > @ ( ∔ 4 ) + D > 7
y rosbmvgoahb osto sgston` bdtoaonbs @ > -4 , D > ?
pbr mb t`atb c(x,y) > -4y + ? , quo sokurb os `rnöagf` pbr sor m` p`rto gn`kga`rg` ho m` cuafgöa `a`mîtgf` -4 z + ?g y funpmo m`s fbahgfgbaos oxgkgh`s sbdro m` crbator` ho H.
• Oeorfgfgbs 60- `) L`mm`r ua` cuafgöa `rnöagf` songpm`ab x 1 9 quo vorgcgquo5
K(x,y) hocgagh` oa om
K(9,y) > 0 sg y 1 9 K(9,y) > 4 sg y = 9
y
K>0 x
K>4
d) L`mm`r ua` cuafgöa `rnöagf` N(x,y) hocgagh` oa om songpm`ab y 1 9 quo vorgcgquo5
N>4
N(x,9) > 0 sg x 1 9 , N(x,9) > 4 sg x = 9 f) L`mm`r ua` cuafgöa `rnöagf` fu`hr`ato quo vorgcgquo5 J(x,9) > 0 sg x 1 9
N>0
x
J(x,y) hocgagh` oa om prgnor y
J>4
J(9,y) > 4 sg y 1 9
x
J>0 h) L`mm`r ua` cuafgöa `rnöagf` L(r,μ) hocgagh` oa @ > {(r,μ) / r 1 9 , ω / 3 = μ = ω / 6 } quo vorgcgquo5
L(r , ω / 3) > ∔4
L(r, ω / 6) > 6
Oxpros`r L oa cuafgöa ho
y
L>6 L>-4
x o y
x y
o) L`mm`r uas cuafgöa `raöagf` S(x,y) hocgagh` oa D > {(x,y) / 0 = x4 + y4 = 8} quo vorgcgquo5
S > ? sbdro x4 + y4 > 0 4
4
S>? 0
4
x
S > 0 sbdro x + y > 8
S>0 64
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
c) ²Puç cuafgöa `rnöagf` prbpbahrî` oa mbs oeorfgfgbs `atorgbros sg mbs v`mbros sbdro m` crbator` cuor`a5 `0) K(9,y) > 3 , p`r` tbhb y f0) J(9,y) > J(x,9) > 9 , p`r` x 1 9 , y 1 9 64- L`mm`r ua` cuafgöa `rnöagf` vorgcgquo5
d0) N(x,9) > -4 , p`r` tbhb x
L(x,y) hocgagh` oa m` cr`ae`5 - ∑ = x = ∑ , ` = y = d quo
4 sg y > ` L ( x, y ) > 8 sg y > d 66- Tosbmvor om oeorfgfgb 6060- f) tr`ascbrn`ahb tr`ascbrn`ah b om prgnor fu`hr`ato oa om songpm`ab suporgbr y muokb `pmgf`r om oeorfgfgb 60-d) y
68- L`mm`r m` oxprosgöa ho m` tonpor`tur` ost`fgba`rg` oa 4 4 om gatorgbr ho ua fgmgahrb fuy` soffgöa tr`asvors`m os x + y > 0 ho nbhb quo vorgcgquo5 X(x,y) > 099 oa x4 + y4 > 0 fba y 1 9
X(x,y) > 9
oa
X>099 x
x4 + y4 > 0 fba y = 9
X>9
Gahgf`fgöa5 M` ofu`fgöa hgcoroafg`m quo hodo s`tgsc`for ua` tonpor`tur` ost`fgba`rg` X(x,y) os ∋ 4 X(x, y ) > 9. Xr`ascbrn`r om fîrfumb oa om songpm`ab suporgbr ho n`aor` quo m` songfgrfuacoroafg` gacorgbr so tr`ascbrno oa om oeo ro`m pbsgtgvb
6?- L`mm`r m` oxprosgöa ho m` tonpor`tur` ost`fgba`rg`
y
X(x,y) oa m` rokgöa oxtorgbr ho ua fgmgahrb fuy` soffgöa tr`asvors`m os
x4 + (y-0)4 > 0 ho nbhb quo 4 4 vorgcgquo5 X(x,y) > 099 oa x + (y-0) > 0 X(x,y) > 9
oa
y > 9
Gahgf`fgöa5 Xr`ascbrn`r om rofgatb utgmgz`ahb
X>9
w > 0/z
63- L`mm`r m` oxprosgöa hom pbtoafg`m omoftrbstàtgfb S(x,y) oa om osp`fgb fbnproahghb oatro hbs fgmgahrbs fbahuftbros fb`xg`mos | z | > 0 , | z | > 4 fu`ahb so s`do quo5
oa
|z | > 0
, S(x,y) > 09
X>9
y
oa
|z | > 4
x
S>9 0
∋ 4 S (x, y ) > 9 oa 0 = | z | = 4
S(x,y) > 9
X>09
g
4
S>09
x
66
Nöhumb G- _agh`h 4
N`tonàtgf` H y H0
6;- L`mm`r m` hgstrgdufgöa ost`fgba`rg` ho m` tonpor`tur`
y
X(x,y) oa m` rokgöa sbndro`h` ho m` cgkur` quo vorgcgquo5 X(x,9) > 9
oa
X>89
| To(z) | 10
S(x,y) > 899 oa |z | > 0 , Gn(z) 1 9
X > 9 -0
X>9
0
x
•• •• Oeorfgfgbs `hgfgba`mos 6
{ z / | z + 0 | ≯ 0 y | z | ≨ 4 } pbr w >
8g z+4
d) L`mm`r ua` cuafgöa `rnöagf` X(x,y) oa om gatorgbr hom fbaeuatb @ ho nbhb quo5 X(x,y) > -4 sbdro | z + 0 | > 0 , X(x,y) > 6 sbdro | z | > 4 hbaho z > x + g y
67`) L`mm`r ua` tr`ascbrn`fgöa w > c(z) quo oavîo om fbaeuatb @> {(x,y) / 0 ‖ y ≨ x ≨ y -0 } oa om fbaeuatb D> { w / Gn (w) ≨ 9 } ho nbhb quo c(g) > 9 d) L`mm`r, ua` cuafgöa `rnöagf` X(x,y) oa om gatorgbr hom fbaeuatb @ ho nbhb quo5 X > -0 sbdro m` songrroft` y > 0 + x , x 1 9 : X > -4 sbdro m` songrroft` y > 0 ‖ x , x = 9. Eustgcgf`r quo os `rnöagf`.
68
Nöhumb G- _agh`h 4
N`tonàtgf` H
N@XONÀXGF@ H Nöhumb G5 @aàmgsgs ho S`rg`dmo Fbnpmoe`
_agh`h 6
Gatokr`fgöa Fbnpmoe` N`k. N`rî` Gaçs D`r`k`ttg D`r`k`ttg
♣
Gatokr`m ho ua` cuafgöa cua fgöa ho v`rg`dmo ro`m ` v`mbros fbnpmoebs
♣ Vo` z(t) > u(t) + g v(t) ua` cuafgöa ho v`rg`dmo ro`m t ` v`mbros fbnpmoebs, fba u(t) y v(t) gatokr`dmos oa Z`,d^ , so hocgao m` gatokr`m ho z(t) oa Z`,d^ fbnb5 d
d
d
∪` z(t ) ht > ∪` u(t ) ht + g ∪` v(t ) ht Oeonpmbs
0-
4
4
4
4
4
4 4 4 6 ∪∔0 (8t + g6t ) ht > ∪∔08t ht + g ∪∔06t ht > 4t ∔0 + gt ∔0 > 3 + g7 ω
ω
soa fbs(at ) (at ) ( ∔0) a ∔ 0 4- ∪ (fbst + gsoa t ) ht > ∪ Zfbs (at) + g soa (at)^ ht > ∔g >9∔g 9 9 a 9 a 9 a ω
ω
a
∃ @ftgvgh`h 05 `) Vg z0(t) > u0(t) + g v0(t)
y z4(t) fbast`atos fbnpmoe`s honbstr`r quo 5 d
> u4(t) + g v4(t) sba gatokr`dmos oa Z`,d^ y ΰ y δ sba
d
d
∪` Zΰ z 0 (t ) + δ z 4 (t)^ ht > ΰ ∪` z 0 (t ) ht + δ ∪` z 4 (t) ht (prbpgoh`h ho mgao`mgh`h) z(t) > u(t) + g v(t) os gatokr`dmo oa Z`,d^ , honbstr`r m`s sgkugoatos prbpgoh`hos5
d) Vg d0) d6)
To ∪` z(t ) ht > ∪` ToZz(t )^ ht d4) Gn ∪` z(t ) ht > ∪` GnZz(t )^ ht d
d
d
d
∪` z(t ) ht > ∪` z(t) ht
d
d
0
Nöhumb G - _agh`h 6
N`tonàtgf` H
∃ @ftgvgh`h 45 d
Vg z(t) os gatokr`dmo oa
Z`,d^ oatbafos v`mo m` sgkugoato hosgku`mh`h
`
∪
d
z(t ) ht ≨ ∪` z(t ) ht
@ fbatgau`fgöa so dbsquoe` m` honbstr`fgöa ho ost` prbpgoh`h y so hoe` ` f`rkb hom `munab eustgcgf`r `mkuabs ho mbs p`sbs.
μ9, , os hofgr
d
∪` z(t ) ht > r9o
gμ 9
d
∪` z(t ) ht os ua fbnpmoeb ho nöhumb r9 y `rkunoatb d g d y > r (#) z ( t ) ht 9 ∪` o z(t ) ht > r9 (##) ∪`
Vupbak`nbs quo om rosumt`hb ho m` gatokr`m
⇔
∔ μ9
Xoagoahb oa fuoat` (#) y (##) y btr`s prbpgoh`hos y` noafgba`h`s, eustgcgf`r tbh`s m`s gku`mh`hos y hosgku`mh`hos quo so gahgf`a ` fbatgau`fgöa5 d
∪`
z(t ) ht >
( 0)
d ∔ gμ 9
∪` o
d
z(t ) ht > To ∪` o ∔gμ9 z(t ) ht > ∪` To Zo ∔ gμ9 z(t )^ht ≨ ∪` o ∔ gμ9 z(t ) ht > ( 4) (8) (?) ( 6) d
d
d
∪ z(t) ht `
(0)5pbr (#) y (##) (4)5…………………………………………………… (4)5…………… ………………………………………………………………………… …………………………………………… ………… (6)5…………………………………………………… (6)5…………… ………………………………………………………………………… …………………………………………… ………… (8)5…………………………………………………… (8)5…………… ………………………………………………………………………… …………………………………………… ………… (?)5…………………………………………………… (?)5…………… ………………………………………………………………………… …………………………………………… …………
∃ @ftgvgh`h 65 z(t) os fbatgau` oa Z`,d^ y sg U(t) os ua` prgngtgv` ho z(t), os hofgr U‗(t) > z(t) , oatbafos d ∪` z(t ) ht > U(d) ∔ U(`)
Vg
_s`r oa tbhbs mbs f`sbs m` hocgagfgöa ho gatokr`m h`h` nàs `rrgd`. Ost` prbpgoh`h , fbnb oa om f`sb ho cuafgbaos ro`mos, so hoabnga`
Tokm` ho D`rrbw.
Oeonpmb
Fbabfgoahb m` rokm` ho D`rrbw p`r` cuafgbaos ho v`rg`dmo ro`m ` v`mbros fbnpmoebs, pbhonbs l`mm`r m` gatokr`m prbpuost` oa om oeonpmb 4 hom sgkugoato nbhb5
o gat ∪9 (fbst + gsoa t ) ht > ∪9 (o ) > ∪9 o ht > ga ω
a
ω
gt a
ω
gat
ω
sg a os p`r (∔ 0)a ∔ 0 9 > > ga 4g/a sg a os gnp`r
9
4
Nöhumb G - _agh`h 6
N`tonàtgf` H
∃ @ftgvgh`h 85 ho ofu`fgöa `) Vg ζ d ζ os ua `rfb ho furv` su`vo g y(t) fba | hz |> z' (t ) ht > mbakgt z(t) uh h>omx(t) `rfb+ ζ honbstr`r quo ζ
∪
∪`
ζ ζ
N os ua` fbast`ato pbsgtgv` y |z(t)| ≨ N p`r`
d) Vg
` ≨ t ≨ d, f`mfum`r |z' (t)| y
` ≨ t ≨ d, honbstr`r quo
d
∪` z(t ) ht ≨ N (d ‖ `) ♣
Gatokr`m ho ua` cuafgöa cua fgöa ho v`rg`dmo fbnpmoe` sbdro ua` furv`
ua `rfb ho furv` su`vo ho ofu`fgöa p`r`nçtrgf` z(t) > x(t) + g y(t) fba ` ≨ t ≨ d y ♣ Vo` ζ ζ ua sbdro om `rfb ζ c(z) ua` cuafgöa fbatgau` sbdro ζ ζ, so hocgao m` gatokr`m ho c sbdro ζ fbnb5 d
∪
ζ ζ
d
∪
∪
c(z) hz > `c ( z(t )) hZz(t)^ > `c ( z(t )) z' (t) ht
Oeonpmb
Y`r` f`mfum`r m` gatokr`m
∪ Zz - To(z) - g ^hz , ζ ζ
sgoahb ζ ζ om soknoatb ho ofu`fgöa p`r`nçtrgf`
z(t) > 4t + g (8t ‖ 0) fba -0 ≨ t ≨ 4 us`nbs m` hocgagfgöa ho gatokr`m p`r` tr`ascbrn`rm` oa ua` gatokr`m ho ua` cuafgöa ho v`rg`dmo ro`m ` v`mbros fbnpmoebs fbnb so nuostr` ` fbatgau`fgöa5 4
4
∪ζ Zz - To(z) - g ^hz > ∪∔0 Zz(t) - To(z(t)) - g^ z' (t) ht > ∪-0 Z4t ∔ g(8t ∔ 0) ∔ 4t ∔ g ^ (4 + g 8) ht > ζζ
∔
4
4
4
∔0
∔0
> ∪ - g8t ( 4 + 8g ) ht > ∪ (03t ∔ > 48 -04 g
♣ Yrbpgoh`hos 0- Yrbpgoh`h ho mgao`mgh`h5 Vg c(z) y k(z) sba hbs cuafgbaos gatokr`dmos sbdro m` furv` ζ ζ y ΰ y δ sba hbs fbast`atos fbnpmoe`s oatbafos oatbafos
∪ Zΰ c(z) + δk(z)^ hz > ΰ ∪ c(z) hz + δ∪ k(z) hz ζ ζ
4-
ζ ζ
ζ ζ
Nöhumb ho ua` gatokr`m 5 om nöhumb ho ua` gatokr`m s`tgsc`fo m` sgkugoato hosgku`mh`h5
∪ c(z) hz ≨ ∪ c(z) hz ζ ζ
ζ ζ
6
Nöhumb G - _agh`h 6
N`tonàtgf` H
∃ @ftgvgh`h ?5 Eustgcgf`r m`s prbpgoh`hos 0- y 4- `atorgbros us`ahb m` hocgagfgöa y m`s prbpgoh`hos ho m`s gatokr`mos ho cuafgbaos ho v`rg`dmo ro`m ` v`mbros fbnpmoebs.
Oeonpmbs
o 4gz hz Honbstr`r quo mîn ∪ 4 hz > 9 sgoahb F m` songfgrfuacoroafg` z > T ogt , 9 ≨ t ≨ ω T ↔∑ F z ∔ 4 z + 4 Y`r` pbhor honbstr`r mb sbmgfgt`hb tr`t`nbs ho `fbt`r om nöhumb ho m` gatokr`m us`ahb m` prbpgoh`h 4 y rofbrh`ahb quo om nöhumb ho ua fbfgoato os gku`m `m fbfgoato ho mbs nöhumbs5 4 gz 4 gz
4 gz
∪F z 4o∔ 4 zhz+ 4 hz ≨ ∪F z 4 ∔o4z + 4
hz >
∪F
4
o
F
hz > (#)
z ∔ 4z + 4
T
@ fbatgau`fgöa `fbt`nbs om aunor`hbr y om hoabnga`hbr |o4gz| > |o4gx o-4y| > |o4gx| |o-4y| > 0 . o-4y > o-4y ≨ 0 puos 4
Tofbrh`r quo5
4
4
y ≯9
4
z ∔ 4z + 4 ≯ z ∔ 4z ∔ 4 > z ∔ 4 z ∔ 4 > T ∔ 4T ∔ 4 , pbr mb t`atb
o 4gz 4
z ∔ 4z + 4
≨
|` ° d | ≯ | |` | - | d| |
0 y us`ahb ost` `fbt`fgöa hom gatokr`ahb pbhonbs T ∔ 4T ∔ 4 4
fbatgau`r fba m` gatokr`m fbnb so nuostr` ` fbatgau`fgöa5 (#) >
∪F
0 0 > hz T 4 ∔ 4T ∔ 4 T 4 ∔ 4T ∔ 4
∪F
hz >
046
mbakgtuh ho F
ωT
T 4 ∔ 4T ∔ 4
ωT o 4gz hz ≨ 4 Lonbs pbhghb honbstr`r quo 9 ≨ ∪ 4 hz F z ∔ 4z + 4 T ∔ 4T ∔ 4 Fbnb oa ost` õmtgn` cr`ffgöa om kr`hb hom hoabnga`hbr os n`ybr quo om kr`hb hom aunor`hbr , tbn`ahb mîngto p`r` T↔∑ ↔∑ oa ost` õmtgn` hosgku`mh`h y us`ahb om tobron` hom s`ahwgfl , pbhonbs `cgrn`r quo so funpmo mb pohghb.
8
Nöhumb G - _agh`h 6
N`tonàtgf` H
⊟ Tom`fgöa oatro m` gatokr`m ho ua` cuafgöa ho v`rg`dmo fbnpmoe` y m` gatokr`m
ho mîao` ho cuafgbaos ro`mos Fbasghor`ahb z > x + g y , c(z) > u(x,y) + g v(x,y) y hz > hx + g hy , m` gatokr`m ho c(z) sbdro m` furv` ζ puoho oxpros`rso fbnb ua fbnpmoeb fuy` p`rto ro`m o gn`kga`rg` sba gatokr`mos ho mîao` ζ puoho ho cuafgbaos ho hbs v`rg`dmos ro`mos fbnb so nuostr` ` fbatgau`fgöa5
∪ c(z) hz > ∪ Zu(x, y) + g v(x, y)^ (hx + g hy) > ∪ Zu(x,y) hx - v(x,y) hy ^ + g Zv(x, y) hx + u(x, y) hy ^ > > Zu(x, y) hx - v(x, y) hy ^ + g Zv( x, y )hx + u(x, y) hy ^ ∪ ∪ ζ ζ
ζ ζ
ζ ζ
ζζ
ζ ζ
♣ Yrbpgoh`hos (fbatgau`fgöa) 6-
F`ndgb ho brgoat`fgöa ho m` furv` 5 Vg ζ ζ y -ζ ζ roprosoat`a m` ngsn` furv` porb rofbrrgh` oa soatghbs fbatr`rgbs oatbafos
∪ c(z) hz > ∔∪ c(z) hz ζ ζ
8-
∔ ζ ζ
Yrbpgoh`h `hgtgv` ho m`s furv`s5 Vg ζ ζ0 y ζ ζ4 roprosoat`a hbs
ζ ζ0
furv`s brgoat`h`s quo tgoaoa ` mb sunb ua aõnorb cgagtb ho puatbs oa fbnõa oatbafos5
∪
∪ c(z) hz + ∪ c(z) hz
c(z) hz >
ζ ζ 0 ∥ ζ ζ 4
ζ ζ 0
ζ ζ4
ζ ζ 4
∃ @ftgvgh`h 35 Eustgcgf`r m`s prbpgoh`hos 6- y 8- `atorgbros toagoahb oa fuoat` quo m`s ngsn`s prbpgoh`hos sba vàmgh`s oa om f`npb ro`m.
Oeonpmbs
y g
0- F`mfum`r
4
∪ Gn(z) hz , sgoahb ζ ζ 5 5 x > y -0 ζ ζ
Vg p`r`notrgz`nbs m` furv` tbn`ahb
hosho
g l`st` -g
-g
x
y > t , oatbafos om trbzb ho p`ràdbm` quo abs gatoros` tgoao
4
ofu`fgöa p`r`nçtrgf` z(t) > (t -0) + g t fba -0 ≨ t ≨ 0 porb l` quoh`hb n`m brgoat`h`, pbr ommb m` hoabnga`nbs -ζ ζ y bpor`nbs fbnb so nuostr` ` fbatgau`fgöa 5 ?
Nöhumb G - _agh`h 6
N`tonàtgf` H
0
0
∪ζ ζ Gn(z) hz > ∔∪∔ζ ζ Gn(z) hz > ∔∪∔0 Gn( z(t ))z' (t ) ht > ∔∪∔0 t (4t + g ) ht > ∔8 / 6 4- F`mfum`r
∪ 0z hz , sgoahb ζ ζ 5 5 | z | > 4 rofbrrgh` oa soatghb `atglbr`rgb ζ ζ
Y`r`notrgz`nbs m` furv`, oa osto f`sb os ua` fgrfuacoroafg` ho r`hgb 4 5
z(t) > 4 ogt , 9 ≨ t ≨ 4ω 4ω
4ω 0 4ω 0 4ω 0 4ω 0 o 4gt gt gt 4gt ∪ζ ζ z hz > ∪9 z(t ) z' (t ) ht > ∪9 4o gt 4go ht > ∪9 4o ∔gt 4go ht > ∪9 go ht > g 4g > 9 9
?- Gahopoahoafg` hom f`ngab Om fbafoptb ho gahopoahoafg` hom f`ngab y` cuo ostuhg`hb fba m`s gatokr`mos ho mîao` ho v`rg`dmo ro`m, ab bdst`ato rofbrhonbs quo5
♣ Vo hgfo quo ua fbaeuatb `dgortb H os ua hbngagb sg p`r` tbhb p`r ho puatbs ho H oxgsto ua` furv` fbatoagh` oa H quo mbs uao.
♣ _a hbngagb H os sgnpmonoato fbaoxb sg tbh` furv` forr`h` fbatoagh` oa H oafgorr` sömb puatbs ho H.
Ybr oeonpmb bdsorv`ahb mbs sgkugoatos kràcgfbs, so puoho hofgr quo5 H0 os ua hbngagb sgnpmonoato fbaoxb, H4 os ua hbngagb porb ab os sgnpmonoato fbaoxb y H > H6 ∥ H8 ab os ua hbngagb.
H4
H6
H8
H0
H > H6 ∥ H8 ♣ M` gatokr`m
∪ c (z )hz os gahopoahgoato hom f`ngab oa ua hbngagb H sg p`r` tbhb p`r ho ζ ζ
puatbs z0 y z4 hom hbngagb H m` gatokr`m tbn` sgonpro om ngsnb v`mbr sbdro fu`mqugor furv` fbatoagh` oa H quo uao z0 y z4
Muokb ho ost` õmtgn` hocgagfgöa, m` prokuat` a`tur`m os5
²fönb s`dor sg m` gatokr`m ho ua`
cuafgöa ho v`rg`dmo fbnpmoe` os gahopoahgoato hom f`ngab oa ua hbngagb H2 Y`r` pbhor rospbahor ost` prokuat` toaonbs v`rg`s pbsgdgmgh`hos quo hosfrgdgnbs ` fbatgau`fgöa. 3
Nöhumb G - _agh`h 6
N`tonàtgf` H
Α Xobron` 0
5 Fbahgfgöa aofos`rg` y sucgfgoato p`r` quo m` gatokr`m so` gahopoahgoato hom f`ngab
Vo`
oa ua hbngagb H. _a` gatokr`m ho mîao` ho c(z) os gahopoahgoato hom f`ngab oa H ⇘c(z) m` fbatgau` gatokr`m ho c(z) sbdro fu`mqugor furv` forr`h` fbatoagh` oa H v`mo forb.
∃ @ftgvgh`h ;5 Honbstr`r om tobron` 0. (m` honbstr`fgöa os ghçatgf` `m tobron` sgngm`r vgstb oa v`rg`dmo ro`m).
ΑXobron` 4 5 Fbahgfgöa sucgfgoato p`r` quo m` gatokr`m so` gahopoahgoato hom
f`ngab - Tokm` ho D`rrbw.
Vg c(z) os fbatgau` oa ua hbngagb H y oxgsto C(z) oa H t`m quo C‗(z) > c(z) (fbnb oa m` v`rg`dmo ro`m, hofgnbs quo C(z) os ua` prgngtgv` ho c(z)) y ζ os ua` furv` fbatoagh` oa H quo uao z9 fba ζ os
∪
z0 oatbafos c ( z )hz > ζ ζ
∪
z0 z9
c ( z ) hz > C(z 0 ) ∔ C(z 9 ) .
Fbnb om rosumt`hb ho m` gatokr`m hopoaho sömb hom puatb gagfg`m y hom puatb cga`m ho m` furv`, pbhonbs `sokur`r quo5 sg c(z) os fbatgau` oa H y oxgsto ua` prgngtgv` oa H oatbafos m` gatokr`m os gahopoahgoato hom f`ngab oa H.
∃ @ftgvgh`h x(t) + g y(t) , fba ` ≨ t ≨ d , t`m quo z(`) > z9 , oatbafos prbpbaonbs eustgcgf`r tbh`s m`s gku`mh`hos quo so gahgf`a ` fbatgau`fgöa 5 d
d
z(d) > z0
d
∪ζ ζc (z)hz > ∪` c (z(t)) z'(t) ht > ∪` C'(z(t)) z'(t) ht > ∪` ZC(z(t))^' ht >C(z(d)) ∔ C(z(`)) > C(z0 ) ∔ C(z 9 ) (0)
(4)
( 6)
( 8)
(?)
(0)5 ………………………………….………………………… (4)5……………………………………………………………… (6)5 pbr rokm` ho m` f`hoa` so s`do quo ZC(z(t))^‗> C‗(z(t)) z‗(t) (8)5 fbnb C‗(z(t)) os ua` cuafgöa ho v`rg`dmo ro`m ` v`mbros fbnpmoebs y C(z(t)) os ua` prgngtgv`, puoho `pmgf`rso m` rokm` ho D`rrbw
(?)5……………………………………………………………… ;
Nöhumb G - _agh`h 6
N`tonàtgf` H
Oeonpmbs
6z 4 hz , sgoahb ζ ζ om trbzb ho p`ràdbm` y > 0 - x 4 hosho (-0,9) ` (9,0)
0- F`mfum`r ζ ζ
∪
Fbnb c(z) > 6 z4 os fbatgau` oa F y tgoao prgngtgv` C(z) > z6 D`rrbw sgoahb z9 > (-0, 9) > -0 y z0 > (9,0) > g , pbr mb t`atb5
∪ 6z
4
, pbhonbs `pmgf`r om X. ho
hz > C(g) ‖ C(-0) > g6 ‖ (-0)6 > -g + 0
ζ ζ
0 5 | z | > 0 hz , sgoahb ζ ζ 5 4 ζ ζ z
∪
4- F`mfum`r
, puos os fbatgau` oa F ‖ {9} , y C(z) > M` cuafgöa c(z) > 0/z4 os fbatgau` sbdro m` furv` ζ ζ , 0/z os ua` prgngtgv`, pbr mb t`atb puoho `pmgf`rso om X. ho D`rrbw y fbnb m` furv` os forr`h` m` gatokr`m v`mo 9 (forb), puos om puatb gagfg`m fbgafgho fba om puatb cga`m. 6- F`mfum`r
0 5 | z | > 0 hz , sgoahb ζ ζ 5 ζ ζ z
∪
M` cuafgöa c(z) > 0/z os fbatgau` sbdro m` furv` ζ , puos os fbatgau` oa om hbngagb H > F ‖ ζ , {9}, porb oa osto hbngagb ab os pbsgdmo oafbatr`r ua` cuafgöa C(z) t`m quo C‗(z) > 0/z (rofbrh`r quo (Ma z)‗> 0/z s`mvb oa mbs puatbs hom oeo ro`m aok`tgvb), pbr mb t`atb ab puoho `pmgf`rso om X. ho D`rrbw. Ost` gatokr`m hodo f`mfum`rso p`r`notrgz`ahb m` furv` ζ ζ 55 z(μ) > og μ fba 9 ≨ μ ≨ 4ω , f`mfum`ahb z‗(μ) > g og μ y us`ahb m` hocgagfgöa5
0 hz > ζ ζ z
∪
∪
4ω
9
4ω 0 gμ μ > g o h g hμ > g4ω 9 o gμ
∪
Α Xobron` 6 5 Oxgstoafg` ho prgngtgv` Vg c(z) > u(x,y) + g v(x,y) os fbatgau` oa ua hbngagb H y m` gatokr`m ho c(z) os gahopoahgoato hom f`ngab oa H oatbafos oxgsto C(z) oa H t`m quo C‗(z) > c(z) (fbnb oa m` gatokr`m ro`m, so hgfo quo C(z) os ua` prgngtgv` ho c(z)) . @honàs sg z9 os ua puatb fu`mqugor` ho H so vorgcgf` quo
h z c (z *) hz * > c ( z ) ∪ z hz 9 Honbstr`fgöa
<
Nöhumb G - _agh`h 6
N`tonàtgf` H
Fbnb m` gatokr`m
∪ c (z )hz os gahopoahgoato hom f`ngab oa H y s`donbs quo ζ ζ
Zu(x, y) hx - v(x, y) hy ^ + g Zv( x, y )hx + u(x, y) hy ^
c (z )hz > ζζ
∪
ζζ
ζζ
∪
∪
oatbafos m`s gatokr`mos ro`mos
∪ Zu(x, y) hx - v(x, y) hy^ y ∪ Zv(x, y) hx + u(x, y) hy^ ζ ζ
sba gahopoahgoatos hom f`ngab oa H
ζ ζ
(fuostgba`r ost` `cgrn`fgöa, ²os pbsgdmo quo ost`s gatokr`mos ro`mos ab so`a gahopoahgoatos hom f`ngab2) Fbnb m`s gatokr`mos ro`mos sba gahopoahgoatos hom f`ngab, so s`do quo m`s oxprosgbaos y u(x,y) hx - v(x,y) hy v(x,y) hx + u(x,y) hy sba hgcoroafg`mos ox`ft`s, os hofgr oxgstoa oa H hbs cuafgbaos _(x,y) y S(x,y) , hoabnga`h`s cuafgbaos pbtoafg`mos, t`m quo5
∄_ ∄_ h_( x, y ) > ∄x hx + ∄ y hy > u( x, y ) hx ∔ v( x, y ) hy , ∄S ∄S hS( x, y ) > hx + hy > v( x, y ) hx + u(x, y ) hy ∄x ∄y ho hbaho so hosproahoa m`s sgkugoatos gku`mh`hos ho (FT)5
∄_ ∄ S ∄_ ∄S > v( x , y ) > > u( x, y ) , ∔ > ∄y ∄x ∄x ∄y Vg fbasghor`nbs C(z) > _(x,y) + g S(x,y) , vonbs quo5
C(z) os horgv`dmo oa H , puos _(x,y) y S(x,y) , fbnb y` vgnbs, funpmoa m`s fbahgfgbaos ho (FT) y tgoaoa horgv`h`s p`rfg`mos fbatgau`s pbr fbgafghgr hgfl`s horgv`h`s fba m` p`rto ro`m
u(x,y) b gn`kga`rg` v(x,y) ho m` cuafgöa fbatgau` c(z)
Ybr sor C(z) horgv`dmo,
s`donbs quo
pbr mb t`atb pbhonbs `cgrn`r quo oxgsto oa @honàs
z
∪z
9
( x ,y )
c (z *) hz * > ∪( x >
9 ,y 9 )
5 C‗(z) >
∄_ ∄S > u( x, y ) + gv( x, y ) > c ( z ) , +g ∄x ∄x
H ua` cuafgöa horgv`dmo C(z) t`m quo C‗(z) > c(z)
Zu(x*, y*) hx * -v(x*, y*) hy *^ + gZv(x*, y*) hx * +u(x*, y*) hy *^>
( x ,y )
∪( x ,y ) h_(x*, y*) + g hS(x*, y*) >_(x,y) - _(x9 , y9) 9
+ g ZS(x,y) - S(x9 , y9)^ >
9
> _(x , y) + gS(x, y) - Z_(x9 , y9) + g S(x9 , y9)^ > C(z) - C(z9) Ybr mb t`atb
z
c (z *) hz * > C(z) - C(z9) , ho hbaho
h
z
c (z *) hz * > C' ( z ) > c ( z )
∪z
hz ∪z 9
9
7
Nöhumb G - _agh`h 6
N`tonàtgf` H
• Oeorfgfgbs 0- F`mfum`r m`s sgkugoatos gatokr`mos5
∪ To(z) hz : ∪ Gn(z) hz : ∪ z hz
oa mbs sgkugoatos
ζ ζ
ζ ζ
ζ ζ
f`sbs5 `) ζ ζ5 z(t) > 0 + gt , 9 ≨ t ≨ 0 d) ζ ζ5 | z | > 0 , rofbrrgh` oa soatghb `atglbr`rgb f) ζ ζ5 | z ‖ ` | > T , rofbrrgh` oa soatghb `atglbr`rgb
Fbavoafgöa5 Fu`ahb ua` furv` os forr`h` y ab so gahgf` m` brgoat`fgöa, hodo rofbrrorso oa soatghb `atglbr`rgb. 4- F`mfum`r
∪
ζ ζ j
Gn(z) hz p`r` j > 0, 4 y 6 hbaho
`) ζ ζ0 os om soknoatb brgoat`hb quo uao 0 fba g d) ζ `atglbr`rgb ζ4 5 | z | > 0 , hosho 0 l`st` g , oa soatghb `atglbr`rgb f) ζ ζ6 os m` pbmgkba`m quo uao 0 fba 9 y 9 fba g h) Xoagoahb oa fuoat` quo ζ ζ0 , ζ ζ4 y ζ ζ6 sba tros furv`s hgstgat`s quo tgoaoa om ngsnb puatb gagfg`m y cga`m, ²puoho `cgrn`r quo m` gatokr`m os gahopoahgoato hom f`ngab2, ²fbatr`hgfo om tobron` cuah`noat`m2
∪F | z |
6- `) F`mfum`r d) Hohufgr
∪F ( x
4
`
4
o g | z | hz sgoahb F5 |z| > 4 hosho 4 ` ‖4 oa soatghb `atglbr`rgb
p`rtgr
ho
`)
om
rosumt`hb
ho
m`
sgkugoato
gatokr`m
?- F`mfum`r
∪ Ma z hz p`r` j > 0 , 4 , 6 ζ ζ j
∔0
∪ζ ζ( z ∔ `) hz > 4ωg ,
sgoahb
3- F`mfum`r5
f)
∪ (z - 4g) hz sgoahb ζ ζ om soknoatb quo uao 4 + g fba 6 ‖ 4g 4 4z ∪F o hz sgoahb F 5 y > 4x hosho (-0, 4) ` (4, 9 p`r` a ≩-0
ζ ζ0 5 | z | > T hosho T l`st` ‖ Tg oa soatghb `atglbr`rgb, ζ ζ4 5 | z | > T hosho T l`st` ‖ Tg oa soatghb lbr`rgb, ζ ζ6 5 | z | > T ,
d)
mîao`
+ y 4 ) soa x 4 + y 4 hx + ( x 4 + y 4 ) fbs x 4 + y 4 hy
8- Vg ζ ζ5 | z - `| > T , fba T ≩ 9, honbstr`r quo
`)
ho
z
09
Nöhumb G - _agh`h 6
N`tonàtgf` H
;- Eustgcgf`r quo5
hz
`) |z | > 4
hz ≨
8ω
6
z +0 ; ω Ma z d) ≨ (4Ma T + ω ) , hz T 4T z4 Ma z mîn ∪F 4 hz > 9 T ↔∑ T z
∪ ∪F
FT 5 z(t) > T o gt , | t | ≨ ω /4
y honbstr`r quo
Α Xobron` ho F`ufly Vo` ζ furv` forr`h`, sgnpmo y su`vo pbr tr`nbs y so` c(z) ua` cuafgöa `a`mîtgf` sbdro ζ ζ ua` furv` ζ y su gatorgbr fuy` horgv`h` c ‗(z) os fbatgau` sbdro ζ ζ y su gatorgbr oatbafos
∪ c(z) hz > 9 ζ ζ
Honbstr`fgöa Y`r` honbstr`r osto tobron` us`nbs om tobron` ho Krooa quo rom`fgba` ua` gatokr`m ho mîao` fba ua` gatokr`m hbdmo5 Xobron` ho Krooa5 Vo` F ua` furv` forr`h`, sgnpmo y rokum`r ` trbzbs (su`vo) fbatoagh` oa ua hbngagb H hom pm`ab y so` T m` rokgöa mgngt`h` pbr F , so`a N(x,y) y A(x,y) hbs cuafgbaos fba horgv`h`s p`rfg`mos fbatgau`s oa H oatbafos
∄A ∄N + > Nhx Ahy ∪F ∪∪T ∄x ∔ ∄y hx hy hbaho F hodo rofbrrorso ho nbhb ho hoe`r ` T ` su gzqugorh`
Vg
F
y
T
H x
c(z) > u(x,y) + g v(x,y) oatbafos s`donbs quo5
∪ c(z) hz > ∪ Zu(x, y) hx - v(x, y) hy ^ + g ∪ Zv(x, y )hx + u(x, y) hy^ > ∔ ∄v ∄u ∄u ∄v hx hy + g ∔ hx hy > 9 + g 9 > 9 > ∔ ∪∪ ∄x ∄y ∪∪ ∄x ∄y ζζ
ζ ζ
(0 )
T
ζ ζ
T
( 4)
(0) @pmgf`ahb om tobron` ho Krooa ` f`h` gatokr`m ro`m (4) Fbnb c(z) os `a`mîtgf`, sus p`rtos ro`m o gn`kga`rg` vorgcgf`a m`s fbahgfgbaos ho (F-T) y pbr mb t`atb f`h` gatokr`ahb v`mo forb.
00
Nöhumb G - _agh`h 6
N`tonàtgf` H
⊟ Bdsorv`fgöa Kburs`t cuo om prgnorb quo puhb honbstr`r quo m` lgpötosgs " c ‗(z) fbatgau` sbdro ζ ζ y su gatorgbr " pbhî` bngtgrso , absbtrbs `fopt`nbs sga honbstr`fgöa m`s sgkugoatos v`rg`atos hom tobron` ho F`ufly
Α Xobron` ho F`ufly Kburs`t (vorsgöa 0) Vg ζ ζ os ua` furv` forr`h`, sgnpmo y su`vo pbr tr`nbs y oatbafos
c(z) os `a`mîtgf` sbdro ζ ζ y su gatorgbr
∪ c(z) hz > 9 ζ ζ
Α Xobron` ho F`ufly Kburs`t (vorsgöa 4) Vg ζ urv` forr`h`, sgnpmo y su`vo pbr tr`nbs y c(z) os `a`mîtgf` sbdro ζ y su gatorgbr , ζ os ua` ffurv` ζ y s`mvb ` mb sunb oa ua aõnorb cgagtb ho puatbs oxfopfgba`mos hbaho os fbatgau` oatbafos
∪ c(z) hz > 9 ζ ζ
Oeonpmbs
o 6z `) M` gatokr`m hz os gku`m ` 9 puos vorgcgf` m`s lgpötosgs hom X. ho F`ufly Kburs`t 5 |z |>0 z - 4g o 6z m` furv` os forr`h` y su`vo y c(z) > os `a`mîtgf` sbdro m` furv` |z| > 0 y su gatorgbr z ∔ 4g
∪
puos ab os `a`mîtgf` oa gatokr`.
4g , porb osto fbnpmoeb os oxtorgbr ` m` furv` forr`h` sbdro m` quo so
d) M` `pmgf`fgöa hom tobron` ho F`ufly Kburs`t ab os t`a ganohg`t` p`r` om fàmfumb ho m`
soa z soa z os `a`mîtgf` sbdro m` furv` forr`h` y su hz , puos m` cuafgöa c(z) > |z | >` z z gatorgbr s`mvb oa z9 > 9 , quo os gatorgbr ` fu`mqugor fgrfuacoroafg` ho r`hgb ` 1 9.
gatokr`m
∪
Vga ond`rkb sg f`mfum`nbs om mgngto ho m` cuafgöa oa hgfl` sgakum`rgh`h bdtoaonbs
soa z soa z sg z ≩ 9 pbhonbs `cgrn`r quo5 mîn > 0 y sg fbasghor`nbs m` cuafgöa k( z ) > z z ↔9 z 0 sg z > 9
k(z) os fbatgau` oa z > 9 y sg z ≩ 9 s`donbs quo k(z) os `a`mîtgf` pbr sor fbfgoato ho
04
Nöhumb G - _agh`h 6
N`tonàtgf` H
`a`mîtgf`s y om hoabnga`hbr ab so `aum`, pbr mb t`atb pbr pbr om X. ho F`ufly Kburs`t pbhonbs `cgrn`r quo
∪ k(z) hz > 9 . |z |> `
Bdsorvonbs quo sbdro mbs puatbs ho m` furv`
m` cuafgöa k(z) fbgafgho m` cuafgöa fuy` soa|z|z > ` , p`r` mbs z quo vorgcgf`a |z| > ` , oatbafos m` gatokr`m quoronbs f`mfum`r, os hofgr k(z) > z soa z . pbr mb t`atb gatokr`m ho k(z) sbdro hgfl` furv` hodo fbgafghgr fba m` gatokr`m ho z soa z hz > k(z) hz > 9 |z | >` |z | > ` z
∪
∪
♣ Fbasofuoafg`s hom Xobron` ho F`ufly T
ζ ζ0
0- Vo`a ζ ζ0 y ζ ζ4 hbs furv`s forr`h`s su`vos pbr tr`nbs y tbhbs mbs puatbs ho ζ ζ0 sba gatorgbros ` ζ ζ4 y so` c(z) ua` cuafgöa `a`mîtgf` sbdro m`s furv`s y oa om hbngagb T mgngt`hb pbr omm`s oatbafos5
∪
ζ ζ 0
c(z) hz > ∪ζ ζ c(z) hz 4
M`s furv`s so rofbrroa oa om ngsnb soatghb (`nd`s oa soatghb `atglbr`rgb b `nd`s oa soatghb lbr`rgb)
Honbstr`fgöa Vupbak`nbs quo ζ ζ0 y ζ ζ4 m`s rofbrronbs oa soatghb `atglbr`rgb. Vg ocoftu`nbs hbs fbrtos roftbs uagoahb puatbs ho ζ ζ0 y ζ ζ4 , om hbngagb T quoh` hgvghghb oa hbs rokgbaos, quo hoabnga`nbs T0 y T4
T0 H
D
F
@
T4 M`s crbator`s ho T0 y T4 sba furv`s forr`h`s y m`s gahgf`nbs ∄T 0 y ∄T 4 rospoftgv`noato.
Fbnb c(z) os `a`mîtgf` sbdro hgfl`s furv`s y su gatorgbr, pbhonbs `pmgf`r om X. ho F`ufly Kburs`t ` `nd`s y bdtoaor quo 5
06
Nöhumb G - _agh`h 6
N`tonàtgf` H
∪ T c(z) hz > 9
∪ T c(z) hz > 9
y
∄ 0
∄ 4
hbaho m`s furv`s ∄T 0 y ∄T 4 m`s brgoat`nbs ho nbhb ho hoe`r m`s rokgbaos gzqugorh`.
T0 y T4 ` m`
∪ T c(z) hz + ∪ T c(z) hz > 9 , y kugàahbabs pbr om kràcgfb
Vun`ahb ostbs rosumt`hbs bdtoaonbs5
∄ 0
∄ 4
pbhonbs osfrgdgr m` õmtgn` gku`mh`h hom sgkugoato nbhb5 @
H
F
D
D
F
H
@
∪D c ( z)hz + ∪@ c (z )hz + ∪H c ( z)hz + ∪F c (z )hz + ∪@ c (z )hz + ∪D c ( z )hz + ∪F c (z )hz + ∪H c (z )hz > 9 (*)
088 8 8 8 8 8 8 488 8 8 8 8 8 8 6
088 8 8 8 8 8 488 8 8 8 8 8 6
sbdro m` crbator` ho T 0
sbdro m` crbator` ho T 4
Fbnb m`s gatokr`mos ho mîao` sbdro mbs soknoatbs so f`afom`a puos so rofbrroa oa soatghbs fbatr`rgbs fu`ahb so fbasghor`a oa m` crbator` ho T0 b oa m` crbator` ho T4 y toagoahb oa fuoat` quo (ngr`r om kràcgfb)5 D
∪F c (z ) hz
F
∪D c (z ) hz
+
ζ ζ 0
sbdro m` crbator` ho T 4
sbdro m` crbator` ho T 0 H
∪@ c (z ) hz
+
0 8 48 6
> ∔ ∪ c ( z ) hz
0 8 48 6
0 8 48 6
sbdro m` crbator` ho T 0
@
∪ c (z ) hz
> ∪ c ( z ) hz
H
ζ ζ 4
0 8 48 6
sbdro m` crbator` ho T 4
hbaho oa m` prgnor` gatokr`m so l` fbmbf`hb ua sgkab noabs puos so bdsorv` quo ζ ζ0 hodo rofbrrorso oa soatghb fbatr`rgb `m quo `auafg`nbs `m fbnoaz`r, vonbs quo m` oxprosgöa (*) tbn` m` cbrn`5 ∔
∪
ζ ζ 0
c(z) hz + ∪ c(z) hz > 9 , y pbr mb t`atb5 ζ ζ 4
∪
ζ ζ
c(z) hz > ∪ζ ζ c(z) hz
4
4
4- Vo`a ζ ζ4 y ζ ζ6 tros furv`s forr`h`s su`vos pbr tr`nbs fbnb ζ0 , ζ so nuostr`a oa om kràcgfb y so` c(z) ua` cuafgöa `a`mîtgf` sbdro m`s furv`s y oa m` rokgöa T mgngt`h` pbr omm`s oatbafos5
ζ ζ6
T
4
+ ∪ c(z) hz ∪ζ ζ c(z) hz > ∪ζ ζ c(z) hz ζ ζ 0
4
6
ζ ζ0 hbaho m`s furv`s so rofbrroa ho nbhb ho hoe`r m` rokgöa T ` m` gzqugorh`.
∃ @ftgvgh`h 9 , ²fba ζ ζ
osto rosumt`hb puoho `cgrn`r quo l`y gahopoahoafg` hom f`ngab2 Oeonpmbs
0- Vg
c(z) ua` cuafgöa `a`mîtgf` oa tbhb om pm`ab y so s`do quo
fbabforso om v`mbr ho m` gatokr`m oafgorr` `
∪|z |>0 >
c(z) hz > ω z
,
²puoho
c(z) hz , sgoahb ζ ζ ua` furv` su`vo pbr tr`nbs, forr`h`, quo ζ ζ z
∪
z>9 2
Os gnpbrt`ato bdsorv`r quo om gatokr`ahb os `a`mîtgfb oa tbhb om pm`ab fbnpmoeb s`mvb oa z > 9 Vg ζ g atorgbr) , fbnb om gatokr`ahb os ζ ab fbrt` ` | z | > 0 ( os oxtorgbr b gatorgbr) `a`mîtgfb oa m` rokgöa fbnproahgh` oatro m` fgrfuacoroafg` | z | > 0 y m`
0
c(z) furv` ζ , `pmgf`ahb m` fbasofuoafg` 0 pbhonbs `cgrn`r quo ∪ ζ , hz > ω ζ ζ z Vg ζ ζ fbrt` ` m` fgrfuacoroafg` | z | > 0, so fbasghor` btr` furv` forr`h`, ` m` quo mm`n`nbs ζ ζ* , fbnb om gatokr`ahb os `a`mîtgfb oa m` rokgöa mgngt`h` pbr | z | > 0 y ζ ζ* , pbr m` fbasofuoafg` 0 , pbhonbs `cgrn`r quo m` gatokr`m
ζ ζ 0
sbdro ζ ζ v`mo ω , fbnb `honàs om gatokr`ahb os `a`mîtgfb oa m` rokgöa mgngt`h` pbr ζ ζ y* ζ ζ* , pbr m` fbasofuoafg` 0 , m` gatokr`m sbdro ζ ζ v`mo mb ngsnb quo m` gatokr`m sbdro ζ * , os hofgr m` gatokr`m sbdro ζ ζ*, ζ v`mo ω Ybr mb t`atb
∪ζ ζ
ζ ζ*
c(z) hz > ω , sgoahb ζ ζ fu`mqugor furv` su`vo pbr tr`nbs, forr`h`, quo oafgorr` ` 9 z
4- Eustgcgf`r , us`ahb m` fbasofuoafg` 4 y toagoahb oa fuoat`
c(z) om kràcgfb ho m` horofl`, quo sg ∪ hz > 6 y ζ ζ 0 (z - 4)(z - g) c(z) c(z) ∪ζ ζ 4 (z - 4)(z - g) hz > ; oatbafos ∪ζ ζ 6 (z - 4)(z - g) hz > - 8 ,
ζ ζ0 g
ζ ζ6 4
4
Vupbaor quo c(z) os `a`mîtgf` ∉z y quo m`s furv`s so rofbrroa oa soatghb pbsgtgvb.
0?
Nöhumb G - _agh`h 6
N`tonàtgf` H
Α Cörnum` ho m` gatokr`m ho F`ufly ζ ζ Vg ζ ζ os ua` furv` forr`h`, sgnpmo y su`vo pbr tr`nbs y c(z) os `a`mîtgf` sbdro ζ ζ y su gatorgbr , y z9 os gatorgbr ` ζ ζ oatbafos
z9
c(z) hz > 4ωg c(z 9 ) ζ ζ z - z 9
∪
Honbstr`fgöa
ζ ζ
Fbasghoronbs ua` fgrfuacoroafg` F foatr`h` oa z9 gatorgbr ` ζ ζ F5 |z ‖ z9 | > T y f`mfum`nbs m` gatokr`m prbpuost` fbnb so nuostr` ` fbatgau`fgöa hbaho f`h` p`sb ostà eustgcgf`hb nàs `d`eb
z9 F
) + c (z 9 ) hz > c(z) - c(z 9 ) hz + c(z ) 0 hz c(z) hz > c(z) hz > c(z) - c(z 9 9 (6) F (0) F z - z ( 4) F F z - z9 ζ ζ z - z z - z9 z - z9 9 9
∪
∪
∪
∪
∪
088 8 488 8 6
@
08486
D
(0)5 sba gku`mos pbr m` prgnor` fbasofuoafg` hom tobron` ho F`ufly puos om fbfgoato c(z) / (z ‖ z9) os `a`mîtgfb sbdro m`s furv`s ζ ζ y F y oa m` rokgöa mgngt`h` pbr `nd`s (4)5 sun`ahb y rost`ahb c(z9) oa om aunor`hbr (6)5 m` gatokr`m ho ua` sun` os sun` ho gatokr`mos y c(z9) os fbast`ato Honbstr`ronbs ` fbatgau`fgöa quo m` gatokr`m tobron` ost`rà honbstr`hb. h onbstr`hb.
@ v`mo forb y m` gatokr`m D v`mo 4ωg y oatbafos om
`) Y`r` eustgcgf`r quo m` gatokr`m @ v`mo forb, fbasghor`nbs m` cuafgöa
c (z ) ∔ c ( z 9 ) sg z ≩ z 9 k( z ) > z ∔ z 9 c ' ( z 9 ) sg z > z 9 @a`mgfonbs ost` cuafgöa k(z)5 sg z ≩ z9 ,
k(z) os `a`mîtgf` pbr sor fbfgoato ho `a`mîtgf`s y om hoabnga`hbr ab so `aum` c ( z ) ∔ c ( z 9 ) k(z) os fbatgau` oa z9 puos mîn k( z ) > mîn > c ' ( z 9 ) > k(z 9 ) z ↔z 9 z↔z 9 z ∔ z9
Ybr mb t`atb k(z) os `a`mîtgf` sbdro m` furv` forr`h` F y su gatorgbr , s`mvb ` mb sunb oa om puatb z9 hbaho s`donbs quo os fbatgau` , pbr ommb pbhonbs `pmgf`r om tobron` ho F`ufly Kburs`t (vorsgöa 4) y `cgrn`r quo
∪ k(z) hz > 9 . F
03
Nöhumb G - _agh`h 6
N`tonàtgf` H
Bdsorvonbs quo sbdro mbs puatbs ho m` furv`
∪F
pbr mb t`atb
F, m` cuafgöa k(z) os gku`m `m fbfgoato gafronoat`m,
c ( z ) ∔ c ( z 9 ) hz > ∪F k(z) hz > 9 , y quoh` honbstr`hb quo m` gatokr`m @ v`mo z ∔ z9
forb. d) Y`r` f`mfum`r m` gatokr`m D, p`r`notrgz`nbs m` fgrfuacoroafg` gt
f`mfum`nbs z'(t) > Tg o y bdtoaonbs 5
∪F
F 5 z(t) > T ogt , fba 9 ≨ t ≨ 4 ω,
4ω 0 4ω 0 gt > hz > ∪9 Tgo ht ∪9 g ht > 4ωg z - z9 To gt
Oeonpmbs
`) F`mfum`r ∪ζ ζ
fbs z hz , sgoahb ζ ζ m` crbator` hom trgàakumb ho vçrtgfos 9 , 8 ° 4g z∔ω
Fbnb om gatokr`ahb tgoao m` cbrn`
8
c(z) , fba c(z) > fbs z , `a`mîtgf` oa tbhb om pm`ab, y z-z 9
, pbhonbs `pmgf`r om X. ho m` cörnum` ho F`ufly z9 > ω ostà oa om gatorgbr ho m` furv` forr`h` ζ ζ , puos so vorgcgf`a tbh`s m`s lgpötosgs , `sî toaonbs5
fbs z
∪ z ∔ ω hz > 4ωg c( ω) > 4ωg fbs(ω) > ∔4ωg ζ ζ
d) F`mfum`r
z6 + 6 ∪|z∔ 4g|>4 z 4 + 0 hz
Oa osto oeorfgfgb om gatokr`ahb ab tgoao m` cbrn`
c(z) , porb sg c`ftbro`nbs om hoabnga`hbr z - z9
vonbs quo5
z6 + 6 z6 + 6 > z 4 + 0 ( z + g )( z ∔ g ) Fbnb om c`ftbr (z - g ) so `aum` oa g, quo os gatorgbr ` m` furv` forr`h` h`h`, y om c`ftbr (z + g) ab so `aum` sbdro m` furv` ag oa su gatorgbr, pbhonbs osfrgdgr m` gatokr`m ho m` sgkugoato n`aor`5
z6 + 6 ∪0z ∔4g|>4 z 4 + 0 hz > ∪0z∔ 4g|>4
z 6 + 6 + z g hz
z∔g
Fbnb (z6 +6) / (z + g) os `a`mîtgf` sbdro m` furv` forr`h` y su gatorgbr , pbhonbs us`r m` cörnum` ho F`ufly. Xbn`ahb c(z) > (z6 +6) / (z + g) om v`mbr ho m` gatokr`m rosumt`5
z 6 + 6 -g+6 > ω > 6 ω ∔ gω > ω > ω hz 4 g c(g) 4 g 4 g ∪0z∔ 4g|>4 4 z + g z >g z +0 4g
z6 + 6
0;
Nöhumb G - _agh`h 6
N`tonàtgf` H
f) F`mfum`r m` gatokr`m h`h` oa d) sbdro m` furv`
F5 | z | > 4
Oa osto f`sb mbs fbnpmoebs g y -g, quo `aum`a om hoabnga`hbr, sba gatorgbros ` m` furv` forr`h`. So`nbs quo ` pos`r ho ostb puoho f`mfum`rso m` gatokr`m nohg`ato m` cörnum` ho F`ufly, p`r` ommb fbasghoronbs hbs furv`s forr`h`s F0 y F4 gatorgbros ` F y hgseuat`s, F0 quo sömb oafgorro ` g y F4 quo sömb oafgorro ` - g . Ybr ua` ho m`s fbasofuoafg`s hom tobron` ho F`ufly Kburs`t, s`donbs quo
z8 + 6 z8 + 6 z8 + 6 ∪F z 4 + 0 hz > ∪F0 z 4 + 0 hz + ∪F4 z 4 + 0 hz
F0
g
F4
-g
fbnb oa om gatorgbr ho m`s furv`s forr`h`s F0 y F4 om gatokr`ahb puoho oxpros`rso fbnb fbfgoato oatro c 0(z) / (z - g) y c 4(z) / (z + g) rospoftgv`noato , ost`s gatokr`mos so f`mfum`r oa cbrn` sgngm`r `m oeonpmb `atorgbr. 8
Vo hoe` fbnb oeorfgfgb vorgcgf`r quo
∪F zz 4 ++ 06 hz > (6ω - gω) + (-6ω - gω) > -4gω
∃ @ftgvgh`h 095
F0
Vg c(z) os `a`mîtgf` oa om `agmmb mgngt`hb pbr hbs fgrfuacoroafg`s fbafçatrgf`s y F4 y z9 os ua puatb gatorgbr ` hgflb `agmmb, honbstr`r quo5
c (z 9 ) >
F0
0 c ( z ) 0 c ( z ) hz hz ∪ ∪ 4ωg F0 z ∔ z 9 4ωg F4 z ∔ z 9
F4
z9
hbaho m`s furv`s so rofbrroa oa soatghb hgroftb. (L`for ua fbrto oa m` rokgöa sbndro`h` y `pmgf`r `mkõa tobron` quo c`fgmgto om fàmfumb ho f`h` gatokr`m)
♣ Koaor`mgz`fgöa ho m` cörnum` ho F`ufly M` cörnum` ho m` gatokr`m ho F`ufly porngto hotornga`r om v`mbr ho ua` cuafgöa `a`mîtgf` oa ua puatb sg fbabfonbs mbs v`mbros quo tbn` hgfl` cuafgöa sbdro ua fbatbrab forr`hb, sgnpmo y su`vo pbr tr`nbs quo gafmuy` ` hgflb puatb. M` cörnum` ho F`ufly puoho koaor`mgz`rso y bdtoaor ua` cörnum` quo porngto f`mfum`r om v`mbr ho tbh`s m`s horgv`h`s ho ua` cuafgöa `a`mîtgf` oa ua puatb sg fbabfonbs mbs v`mbros quo tbn` hgfl` cuafgöa sbdro ua fbatbrab forr`hb, sgnpmo y su`vo pbr tr`nbs quo gafmuy` ` hgflb puatb. M` cörnum` koaor`mgz`h` puoho bdtoaorso nohg`ato m`s sgkugoatos bpor`fgbaos, quo AB
fbastgtuyoa ua` honbstr`fgöa. Vg c(z) os `a`mîtgf` sbdro m` furv` forr`h` y su`vo pbr tr`nbs ζ ζ y su gatorgbr , y z9 os gatorgbr ` ζ ζ , s`donbs quo 0<
Nöhumb G - _agh`h 6
N`tonàtgf` H
c(z) hz . ζζ z - z 9
4ωg c ( z 9 ) > ∪ζ
Vg fbasghor`nbs ` z9 fbnb ua` v`rg`dmo y horgv`nbs m` oxprosgöa `atorgbr rospoftb ho supbaonbs quo pbhonbs gatrbhufgr m` horgv`h` oa om sîndbmb gatokr`m bdtoaonbs5
4ωg c ' ( z 9 ) >
h c(z) h hz > ∪ζ ζ ∪ζ ζ hz 9 z - z 9 hz 9 4ωg c ' (z 9 ) > ∪ζ ζ
z9 y
c(z) c(z) hz ⇔ hz > ∪ζ ζ 4 z z ( ) z z 9 9
c(z) hz (z - z 9 )4
Vg horgv`nbs auov`noato rospoftb ho z9 , bdtoaonbs5
4ωg c ' ' ( z 9 ) >
h hz 9
h c(z) hz ∪ζ ζ > ∪ζ ζ 4 hz 9 (z - z 9 )
4ωg c ' ' ( z 9 ) > 4 ∪ζ ζ
c(z) c(z) hz ⇔ hz > 4 ∪ζ ζ 6 4 ( ) z z ( ) z z 9 9
c(z) hz (z - z 9 )6
Vg horgv`nbs btr` voz abs quoh`5
4ωg c ' ' ' ( z 9 ) > 4
Horgv`ahb
h hz 9
h c(z) > 4 hz ∪ζ ζ ∪ζ ζ hz 9 6 (z - z 9 )
c(z) c(z) c(z) > > 6 ! 3 hz hz ∪ζ ζ (z - z )8 hz ∪ζ ζ (z - z )8 6 (z - z 9 ) 9 9
4ωg c ( a ) (z 9 ) > a! ∪ζ ζ
a vofos so bdtgoao5
Ho hbaho puoho bdtoaorso
ζζ
∪
c(z)
(z - z 9 )a+0
hz >
c(z) hz (z - z 9 )a +0
4ωg c (a) ( z 9 )
a!
Om sgkugoato tobron` rosuno ostbs rosumt`hbs
Α Horgv`h` ho m` cörnum` ho m` gatokr`m ho F`ufly c(z) os `a`mîtgf` sbdro m` furv` forr`h`, sgnpmo y su`vo pbr tr`nbs ζ ζ y su gatorgbr , y z9 os (a) 4ωg c (z 9 ) c(z) gatorgbr ` ζ ζ oatbafos ∪ a +0 hz > ζ ζ a! (z - z 9 )
Vg
⊟ Bdsorv`fgöa5 Vg oa m` õmtgn` c (9) oxprosgöa so roonpm`z` m` cörnum` a > 9 so gatorprot`nbs (z9) fbnb c(z9) y toagoahb oabdtgoao fuoat` quo 9! > 0.ho m` gatokr`m ho F`ufly puos 07
Nöhumb G - _agh`h 6
N`tonàtgf` H
Oeonpmb
F`mfum`r
ζ ζ
∪
o 4gz
hz , sgoahb ζ ζ m` crbator` hom trgàakumb ho vçrtgfos 9 , 8 ° 4g
4
(z ∔ ω) ( z + g ) 6
Vg ox`nga`nbs om hoabnga`hbr vonbs quo om c`ftbr (z + g) ab so `aum` sbdro m` furv` ζ ζ ag oa su 4 gatorgbr. Vga ond`rkb (z - ω) so `aum` oa z > ω , quo os gatorgbr ho ζ ζ, pbr mb t`atb pbhonbs osfrgdgr5
o 4gz ∪ζ ζ (z ∔ ω)4 (z + g ) 6
o 4gz 6 + ( z g ) hz hz > ∪ 4 ζ ζ
(z ∔ ω)
H`hb quo om gatokr`ahb funpmo tbh`s m`s lgpötosgs hom tobron` ho m` horgv`h` ho m` cörnum` ho 4gz 6 F`ufly , mb `pmgf`nbs toagoahb oa fuoat` quo a + 0 > 4, ho hbaho a > 0 , y c(z) > o / ( z + g) .
o 4gz @sî,
( z + g ) 6 hz > 4 ωg c ' ( ω) > 4ωg 4go 4gz ( z + g ) 6 ∔ o 4gz 6( z + g ) 4 > 4ωg 4g( ω + g) - 6 ∪ζ ζ (z ∔ ω)4 (z + g)3 ( ω + g) 8 z > ω
♣ Horgv`h`s ho `a`mîtgf`s Vg c(z) os `a`mîtgf` oa ua puatb z9 , s`donbs quo os `a`mîtgf` oa tbhb ua oatbrab ho z9 , y sg tbn`nbs ua` furv` forr`h`, sgnpmo y su`vo pbr tr`nbs ζ fbatoagh` ζ fbatoagh` oa hgflb oatbrab, pbhonbs `pmgf`r om tobron` `atorgbr bdtoagoahb5
4ωg c (a) (z 9 ) c(z) ∪ζ ζ (z - z )a+0 hz > a! 9
z9 ζ ζ
(a)
@honàs t`ndgça v`mo m` gku`mh`h
hz > 4ωg c (z*) ∪ (z -c(z) a! z *)a 0 ζ ζ
z9
+
sgoahb z* fu`mqugor puatb hom gatorgbr ho m` furv` ζ ζ
z*
ζ ζ
c(z) 4ωg c (4) (z*) y ostb abs hz > Vg tbn`nbs a > 4 oa m` õmtgn` oxprosgöa bdtoaonbs ∪ ζ ζ a! (z - z *)6 gahgf` quo oxgsto m` horgv`h` sokuah` ho c oa tbhb puatb gatorgbr ` m` furv` ζ ζ y pbr mb t`atb m` horgv`h` prgnor` c ' os `a`mîtgf` @pmgf`ahb ua r`zba`ngoatb sgngm`r ` m` cuafgöa `a`mîtgf` c' pbhonbs fbafmugr quo c'' os `a`mîtgf`, y ropgtgoahb om `rkunoatb `atorgbr mmok`nbs `m sgkugoato rosumt`hb cuah`noat`m.
Α Xobron` 5 Horgv`h` ho cuafgbaos `a`mîtgf`s Vg c(z) os `a`mîtgf` oa ua puatb, sus horgv`h`s ho tbhbs mbs örhoaos sba t`ndgça cuafgbaos `a`mîtgf`s oa oso puatb. 49
Nöhumb G - _agh`h 6
N`tonàtgf` H
• Oeorfgfgbs y
F0
∪F c(z) hz 0
7- Vg
x
4
c(z) os `a`mîtgf` oa F ‖ {0, -4, 6g} y
∪|z-0| 0 c(z) hz > 4 , ∪|z 4| 0 c(z) hz > ∔4 , >
+ >
∪|z-6g| 0 c(z) hz > 9 >
`) @vorgku`r om v`mbr ho m` gatokr`m ∪ c(z) hz oa mbs sgkugoatos f`sbs eustgcgf`ahb m` F
rospuost` 5 `0) F os ua` furv` forr`h` fu`mqugor` quo oafgorr` ` 0 y ab oafgorr` ag ` -4 ag ` 6g `4) F os ua` furv` forr`h` fu`mqugor` quo oafgorr` ` 6g y ab oafgorr` ag ` -4 ag ` 0 `6) F os ua` furv` forr`h` fu`mqugor` quo oafgorr` ` 0 y -4 y ab oafgorr` ` 6g `8) F os ua` furv` forr`h` fu`mqugor` quo oafgorr` ` 0, -4 y 6g d) Gahgf`r fm`r`noato mbs pbsgdmos hbngagbs hbaho m` gatokr`m os gahopoahgoato hom f`ngab. 09- F`mfum`r m`s sgkugoatos gatokr`mos oauafg`ahb provg`noato om tobron` b prbpgoh`h quo utgmgz`.
oz
`)
4
hz , F 5 z - 4 > 0
F
∪ oz 4gz f) ∪ hz , F 5 z > 8 Fz∔6 ∔
h)
∪F
o ∔z j
4 z 4 ∔ z 6
( z 4 ∔ 8)
d) F
hz , F 5 z - 4 + g > 0
4
∪ soaz 8(z ) h) ∪ 4 hz , F 5 z > 6 Fz +8
hz , p`r` j > 0 , 4 , F05 |z ‖ 4| > 0 : F45 |z | > 6
c(z) > (z ‖ 4g)8 l(z) hbaho l(z) os `a`mîtgf` y ab so `aum` sbdro m` furv` F y su gatorgbr , c ' (z ) eustgcgf`r quo ∪ hz > 0 F c ( z ) 00- Vg
a > 9, a > 0, a > 4 , m` gatokr`m
04-F`mfum`r p`r`
fbs4z ∪F (z ∔ g )a hz , F5 |z| > 4 oauafg`r provg`noato om
tobron` b prbpgoh`h quo utgmgz`. 40
Nöhumb G - _agh`h 6
N`tonàtgf` H
06- Vg C(z) > g z4 fbs z os ua` prgngtgv` ho
c(z) , f`mfum`r om v`mbr ox`ftb ho
∪F
c(z) hz hbaho F0 0
gω
os ua` furv` quo uao ω o ω fba 4ω . 08- H`h`
G >
(4z - ω) ∪F (z 4 - 0) (0 ∔ soa z ) hz
`) F`mfum`r G us`ahb m` cörnum` ho m` gatokr`m ho F`ufly , s`dgoahb quo F os mb crbator` hom fbaeuatb @ > {z / 0/4 ≨| z | ≨ 6/4 , |@rk(z)| ≨ ω /8} d) ²Yuoho `pmgf`rso m` cörnum` ho m` gatokr`m ho F`ufly p`r` f`mfum`r G sg m` furv` os F 5 | z ‖ 4| > 8/6 2 Eustgcgf`r m` rospuost`. 0?- Vg c(z) os `a`mîtgf` y
z ∔ 4g
k( z ) >
z
, f`mfum`r
c ( z )k' ( z ) ∪|z∔ 4g|>6 k( z ) hz s`dgoahb quo c(4g) > c(9)
Btr`s prbpgoh`hos gnpbrt`atos5 Α Xobron` ho Nbror` Vg c(z) os fbatgau` oa ua hbngagb sgnpmonoato fbaoxb H y p`r` tbh` furv` furv` forr`h` ζ fbatoagh` ζ fbatoagh` oa H so s`do quo
∪ c (z ) hz > 9 oatbafos c(z) os `a`mîtgf` oa H. ζ ζ
Honbstr`fgöa Fbnb m` gatokr`m ho c(z) v`mo forb sbdro fu`mqugor furv` forr`h` fbatoagh` oa H oatbafos pbr Xobron` 0 s`donbs quo m` gatokr`m ho c os os gahopoahgoato hom f`ngab oa H y sg os gahopoahgoato hom f`ngab oa H, pbr Xobron` 6 s`donbs quo oxgsto ua` cuafgöa C(z) `a`mîtgf` oa H t`m quo
C'(z) > c(z) . Fbnb lonbs vgstb quo m` horgv`h` ho ua` cuafgöa `a`mîtgf` os t`ndgça `a`mîtgf` y s`donbs quo os m` horgv`h` ho m` cuafgöa `a`mîtgf` C, so hosproaho quo c os os `a`mîtgf` oa H
c
@fopt`nbs sga honbstr`fgöa m` sgkugoato prbpgoh`h, fbabfgh` fbnb prgafgpgb hom nöhumb nàxgnb
Α Yrgafgpgb hom nöhumb nàxgnb c(z) > u(x,y) + g v(x,y) os `a`mîtgf` y ab fbast`ato oa ua hbngagb `dgortb @ 4 4 oatbafos m` cuafgöa |c(z)| > (u( x, y )) + (v( x, y ) ab pbsoo nàxgnb oa @, os hofgr , ab oxgsto oa Vg ua` cuafgöa
@ ua puatb z9 t`m quo |c(z)| ≨ |c(z9)| ⊛ Bdsorv`fgbaos 44
Nöhumb G - _agh`h 6
N`tonàtgf` H
c(z) > u(x,y) + g v(x,y) oatbafos |c(z)| > v`rg`dmos ro`mos ` m` quo hoabnga`nbs k(x,y)
0- Vg
(u( x, y ))4 + (v( x, y )4
os ua` cuafgöa ho hbs
Os gnpbrt`ato bdsorv`r quo sg oxgstoa oa @ puatbs ho fbbrhoa`h`s (x0, y0) hbaho m`s cuafgbaos u(x,y) y v(x,y) so `aum`a sgnumtàao`noato, os hofgr u(x0,y0) > 9 y v(x0,y0) > 9 oatbafos oa hgflbs puatbs
k( x 0 , y 0 ) > (u( x 0 , y 0 ))4 + (v( x 0 , y 0 )4 > 9 .
Fbnb m` cuafgöa k(x,y) , pbr tr`t`rso ho ua nöhumb, vorgcgf` k(x,y) ≯ 9 p`r` tbhb p`r (x,y) ho @ , y fbnb k(x0,y0) > 9 oatbafos pbhonbs `cgrn`r quo5 k(x,y) ≯ k(x0,y0) , p`r` tbhb p`r (x,y) ho @ y ost` õmtgn` hosgku`mh`h abs hgfo quo m` cuafgöa k(x,y) `mf`az` ua nîagnb oa mbs puatbs (x0, y0) oa mbs fu`mos m`s cuafgbaos u(x,y) y v(x,y) so `aum`a sgnumtàao`noato. 4- Vg ua` cuafgöa c os `a`mîtgf` oa om gatorgbr ho ua fbaeuatb forr`hb y `fbt`hb @ y os fbatgau` sbdro m` crbator` ho @ , oatbafos m` cuafgöa |c(z)| > k(x,y) os fbatgau` oa hgflb fbaeuatb forr`hb y `fbt`hb y so s`do ho m` v`rg`dmo ro`m quo sokurb `mf`az` ua nàxgnb y ua nîagnb `dsbmutb oa @ . Ost`s bdsorv`fgbaos abs porngtoa oauafg`r om sgkugoato tobron`.
Α Xobron` Vg c os ua` cuafgöa fbatgau` oa ua` rokgöa `fbt`h` forr`h` @, y `a`mîtgf` y ab fbast`ato oa om gatorgbr ho @, oatbafos5 `) m` cuafgöa |c(z)| `mf`az` sgonpro ua nàxgnb y bfurro oa `mkõa puatb ho m` crbator` ho @, auaf` oa su gatorgbr, os hofgr oxgsto `m noabs ua puatb z9 oa m` crbator` ho @ t`m quo
|c(z)| ≨ |c(z9)| d) sg `honàs c(z) ≩ 9 oa tbhbs mbs puatbs ho @ , m` cuafgöa |c(z)| `mf`az` sgonpro ua nîagnb y bfurro oa `mkõa puatb ho m` crbator` ho @, auaf` oa su gatorgbr. Vg so omgnga` m` fbahgfgöa c(z) ≩ 9, m` cuafgöa |c(z)| puoho `mf`az`r ua nîagnb oa ua puatb hom gatorgbr ho @ fu`ahb hgflb v`mbr nîagnb os 9.
Oeonpmb
Vg quoronbs s`dor höaho m` cuafgöa c(z) > |z4 - z| `mf`az` ua nàxgnb b ua nîagnb oa om rofgatb forr`hb y `fbt`hb hocgaghb pbr | z | ≨ 0 , fbnoaz`nbs oxprosàahbm` oa cuafgöa ho x o y 5
c(z) > (x + g y)4 - (x + g y) > (x 4 - y4 - x ) + g (4xy -y) y f`mfum`ahb su nöhumb |c(z)| > k(x,y) > (x 4 ∔ y 4 ∔ x ) 4 + ( 4xy ∔ y ) 4 fbnb so s`do quo n`xgngz`r ua` r`îz os oqugv`moato ` n`xgngz`r su r`hgf`ahb , tbn`ronbs m`
cuafgöa k omov`h` `m fu`hr`hb, y fbnb s`donbs quo om nàxgnb mb tbn`rà oa `mkõa puatb ho crbator`, pbhonbs p`r`notrgz`r m` fgrfuacoroafg` | z |> 0 pbagoahb x > fbs t , y > soa t , fba 9 ≨ t ≨ 4ω , y dusf`r mbs nàxgnbs ho m` cuafgöa
Tofbrh`r5 46
> fbs (4t)G - _agh`h 6 fbs4t - soa4 t Nöhumb 4 soa t fbs t > soa (4t)
N`tonàtgf` H
K(t) > Zk(fbs t , soa t)^ 4 > > (fbs 4 t ∔ soa 4 t ∔ fbs t ) 4 + ( 4 fbs t soa t ∔ soa t ) > 4
>
4
(fbs 4t ∔ fbs t ) + ( soa 4t ∔ soa t )
Vo hoe` fbnb oeorfgfgb vorgcgf`r quo mbs puatbs frîtgfbs ho ost` cuafgöa sba t9 > 9 , t0 > ω y pbr mb t`atb mbs pbsgdmos puatbs hbaho om nöhumb tbn` om nàxgnb v`mbr sba5 z9 > (x9,y9) > (fbs 9, soa 9) > (0,9) y z0 > (x0,y0) > (fbsω, soaω) > ( -0, 9) Fbnb | c(z9) |> k(0,9) > 9 y | c(z0) | nàxgnb v`mbr oa om puatb z0 > -0 + g 9 > | c(z)| ≨ 4
> k(-0,9) > 4 , pbhonbs `cgrn`r quo |c(z)| tbn` om -0 , y p`r` tbhbs mbs fbnpmoebs ho |z| ≨ 0, so vorgcgf`
Os gatoros`ato l`for abt`r quo |c(z)| tbn` om nîagnb v`mbr oa om puatb z9 > 0 + g 9 > 0 , puos oa hgflb puatb m` cuafgöa v`mo forb y s`donbs quo pbr tr`t`rso ho ua nöhumb so vorgcgf` 9 ≨ | c(z)| y pbr mb t`atb | c(z9)| ≨ | c(z)| p`r` tbhb z ho |z| ≨ 0 Os gnpbrt`ato l`for abt`r quo oa osto oeonpmb oafbatr`nbs ua nîagnb sbdro m` crbator`, porb sokõa lgfgnbs abt`r oa m` bdsorv`fgöa `atorgbr m` cuafgöa tbn` ua nîagnb oa mbs puatbs hom rofgatb hbaho m`s cuafgbaos u y v so `aumoa sgnumtàao`noato , os hofgr puatbs hbaho c(z) > 9, oa osto f`sb so bdsorv` quo z4 - z > 9 ⇔ z > 9 ö z > 0 , pbr mb t`atb m` cuafgöa pbsoo ua nîagnb t`ndgça oa ua puatb hom gatorgbr ho m` rokgöa.
Α Yrbpgoh`h 5 Nàxgnb ho cuafgbaos `rnöagf`s Vg c(z) > u(x,y) + g v(x,y) os ua` cuafgöa fbatgau` oa ua` rokgöa `fbt`h` forr`h` @ y `a`mîtgf` y ab fbast`ato oa om gatorgbr ho @, oatbafos m`s cuafgbaos u(x,y) y v(x,y) `mf`az`a su nàxgnb oa m` crbator` ho @ y auaf` oa su gatorgbr.
Honbstr`fgöa c(z)
Vg fbasghor`nbs m` cuafgöa k(z) > o , fbnpbsgfgöa ho c fba fba m` oxpbaoafg`m, pbhonbs `cgrn`r quo k os fbatgau` oa @ y `a`mîtgf` y ab fbast`ato oa om gatorgbr ho @, pbr om X. hom nöhumb nàxgnb s`donbs quo |k(z)| > ou(x,y) `mf`az` su nàxgnb oa ua puatb ho m` crbator` ho @. Fbnb m` cuafgöa oxpbaoafg`m os frofgoato, so sgkuo quo om nàxgnb v`mbr ho u(x,y) so `mf`az` oa ua puatb ho m` crbator` ho @. Vg oa f`ndgb fbasghor`nbs m` cuafgöa l(z) > o-gc(z) fuyb nöhumb os | l(z) | > o v(x,y) puoho honbstr`rso oa cbrn` sgngm`r quo om nàxgnb v`mbr ho v(x,y) so `mf`az` oa ua puatb ho m` crbator` ho @.
Α Xobron` ho Mgbuvgmmo Vg c(z) os `a`mîtgf` y `fbt`h` oa tbhb om pm`ab fbnpmoeb oatbafos c(z) os ua` cuafgöa fbast`ato. 48
Nöhumb G - _agh`h 6
N`tonàtgf` H
Honbstr`fgöa Vo` ζ `rdgtr`rgb ζ ua` fgrfuacoroafg` foatr`h` oa ua puatb fu`mqugor` z9 y ho r`hgb `rdgtr`rgb
T, os hofgr
ζ ζ 5 5 | z - z9 | > T .
Fbnb s`donbs quo c os os `a`mîtgf` oa tbhb om pm`ab pbhonbs `pmgf`r m` cörnum` ho m` horgv`h` ho
∪ζ ζ
F`ufly p`r` a > 0 5
c(z) hz > 4 ω g c ' (z 9 ) (z - z 9 )4
Fbnb s`donbs quo c ostà `fbt`h` oa tbhb om pm`ab , s`donbs quo oxgsto ua` fbast`ato pbsgtgv` N t`m quo |c(z)| ≨ N , ostb abs porngto `fbt`r m` gatokr`m `atorgbr fbnb so nuostr` ` fbatgau`fgöa y so hoe` ` f`rkb hom `munab m` eustgcgf`fgöa ho f`h` p`sb5
c ' ( z 9 ) >
c ( z ) 0 c(z) 0 ≨ hz 4ωg ∪ζ ζ (z - z 9 )4 4ω ∪ ζ ζ z ∔ z 9
4
hz ≨
N 0 N N > ωT > 4 hz 4 4 ∪ T 4ω ζ ζ T 4 ωT
pbr mb t`atb pbhonbs `cgrn`r quo p`r` tbhb fbnpmoeb z9 y p`r` tbhb T v`mo 5
9 ≨ |c '(z9)| ≨ N/T
Fbnb N os ua` fbast`ato cge` y T puoho tbn`rso t`a kr`aho fbnb so qugor`, om fbfgoato N/T os t`a forf`ab ` forb fbnb so qugor`, pbr mb t`atb m` õagf` pbsgdgmgh`h os quo c '(z9)> 9 , fbnb z9 os fu`mqugor` sgkagcgf` quo c'(z) > 9 p`r` tbhb z hom pm`ab fbnpmoeb y pbr mb t`atb m` cuafgöa c(z) hodo sor ua` fbast`ato.
• Oeorfgfgbs 03- M` cuafgöa ho v`rg`dmo ro`m c(x) > soa x os horgv`dmo p`r` tbhb | soa x | ≨ 0, ²ostb fbatr`hgfo om X. ho Mgbuvgmmo2 Oxpmgf`r 0;- L`mm`r om nàxgnb y om nîagnb ho |c(z)| oa mbs rofgatbs gahgf`hbs 4
`) d)
y oa | z - 0 | ≨ 4 cc(z) (z)>>fbs z -z6 zoa+ 4@ >oa{(x,y) | z | ≨/ 0 9 ≨ x ≨ 6ω /8 , -0 ≨ y ≨ 4 }
0 { z / |z| ≨ T , 9 ≨ @rk(z) ≨ ω /8}
d)
N`x
DT
H
0 z 4 + 0
sgoahb H > { z / |z| ≨ 0 , 9 ≨ @rk(z) ≨ ω /8} 0
x y ostà `fbt`h` puos
07 - Eustgcgf`r quo
∪ z a hz > 9 , sgoahb ζ ζ fu`mqugor furv` forr`h` quo ab p`s` pbr om brgkoa y a ζ ζ
4, sga ond`rkb m` cuafgöa c(z) > 0 / za ab os `a`mîtgf` oa 9, ²fbatr`hgfo osto loflb om X. ho Nbror`2 os ua a`tur`m cgeb n`ybr b gku`m `
4?
Nöhumb G - _agh`h 6
N`tonàtgf` H
H Fbnpmoe` Nöhumb G5 N@XONÀXGF@ @aàmgsgs ho S`rg`dmo _agh`h 8
Vorgos N`k. N`rî` Gaçs D`r`k`ttg
0- Vufosgbaos ♣ Vo` @ ua fbaeuatb ab v`fîb , ua` sufosgöa hocgagh` omonoatbs ho @ osfrgtbs oa ua brhoa hocgaghb 5
oa @ os sgnpmonoato ua fbaeuatb ho
`0 , `4 , `6 , ........., `a , .......... pbr ommb ua` sufosgöa so puoho fbasghor`r fbnb ua` cuafgöa c fuyb fuyb hbngagb os om fbaeuatb A ho aõnorbs a`tur`mos y su fbhbngagb os @ y vorgcgf` 5 c(0) > `0 , c(4) > `4 , ... , c(a) > `a , ..... Ybr mb koaor`m oa voz ho us`r m` abt`fgöa cuafgba`m c(a) > { `0 , `4 , `6 , ........., `a , ..........} b {`a}a 1 0 b sgnpmonoato {`a}
`a , m` sufosgöa so gahgf`
Om aõnorb tçrngab ho m` sufosgöa , `4 os om koaor`m `0 os omhoprgnor sokuahb. tçrngab y oa koaor`m `a os om a- çsgnb tçrngab m` sufosgöa t`ndgça mm`n`hb tçrngab
@ os ua fbaeuatb ho aõnorbs fbnpmoebs, so hgfo quo m` sufosgöa {`a} os ua` sufosgöa aunçrgf` fbnpmoe` . Vg om fbaeuatb
♣ Vufosgbaos aunçrgf`s fbavorkoatos Vg mbs tçrngabs ho ua` sufosgöa aunçrgf` {`a} so `forf`a ` ua aõnorb M p`r` a sucgfgoatonoato kr`aho, os hofgr sg mîn ` a > M , so hgfo quo m` sufosgöa fbavorko b os fbavorkoato , t`ndgça a ↔∑
puoho hofgrso quo m` sufosgöa fbavorko `m v`mbr sufosgöa hgvorko b os hgvorkoato
M. Ho ab oxgstgr hgflb mîngto, so hgfo quo m`
Os gnpbrt`ato rofbrh`r quo fu`ahb so `cgrn` quo
mîn ` a > M sgkagcgf` quo5 a ↔∑
0
Nöhumb G - _agh`h 8
N`tonàtgf` H
h`hb fu`mqugor aõnorb pbsgtgvb, `m quo so hoabnga` ο, os pbsgdmo oafbatr`r ua aõnorb A (quo hopoaho ho ο ) t`m quo |`a - M | = ο , p`r` tbhb a 1 A
Oeonpmbs 0 + g(a ∔ 0) fbavorko, f`mfum`nbs 5 a
0- Y`r` `vorgku`r sg m` sufosgöa
0 + g(a ∔ 0) > mîn a ↔∑ a ↔∑ a
mîn
0 a ∔0 0 a ∔ 0 + g mîn > 9+g > g + g > mîn a ↔∑ a a↔ ∑ a a a
bdsorv`r quo lonbs us`hb m` prbpgoh`h quo `cgrn` quo om mîngto ho ua` oxprosgöa fbnpmoe`, sg oxgsto, os gku`m ` m` sun` ho mbs mîngtos ho f`h` fbnpbaoato . Fbnb om mîngto oxgsto y os gku`m ` g, hofgnbs quo m` sufosgöa fbavorko fbavorko `m v`mbr
g.
( ∔g ) a 4- Y`r` `vorgku`r sg os fbavorkoato b ab m` sufosgöa `a > a , ab os fbavoagoato dusf`r m` p`rto ro`m y m` p`rto gn`kga`rg` hodghb ` m`s v`rg`fgbaos quo tgoao m` pbtoafg` (-g)a . Gatoatonbs `a`mgz`r m` fbavorkoafg` oxpros`ahb mbs tçrngabs ho m` sufosgöa oa cbrn` pbm`r 5
( ∔g ) a 0 aω ω > y su `rkunoatb `rk(`a) > a `rk (-g) > a ∔ > ∔ f`mfum`nbs su nöhumb |`a| > a a 4 4 ( ∔g ) a 0 - ga4ω 0 0 a ω a ω y oatbafos mîn > mîn o > mîn fbs ∔ g mîn soa > 9 + g 9 > 9 , a↔ ∑ a a↔ ∑ a a ↔∑ a 4 a↔ ∑ a 4 oa om õmtgnb p`sb lonbs us`hb m` prbpgoh`h quo " om prbhuftb ho ua` oxprosgöa quo tgoaho ` forb pbr ua` cuafgöa `fbt`h` tgoaho ` forb", pbr mb t`atb m` sufosgöa fbavorko ` 9 .
∃ @ftgvgh`h 05 `) Honbstr`r us`ahb m` gho` hos`rrbmm`h` oa om oeonpmb 4 quo
mîn | ` a | > 9 ⇔ mîn ` a > 9 ,
sgoahb `a ua` sufosgöa fu`mqugor`. d) Honbstr`r om rofîprbfb ho m` mîn | ` a | > 9 ⇘ mîn ` a > 9
oa
a ↔∑
f) Vg
prbpgoh`h
h`h`
a ↔∑
a ↔∑
`)
y
fbafmugr
quo
a↔∑
`a > ? fbs(aμ) + g ? soa(aμ) , honbstr`r quo m` sufosgöa {|`a|} fbavorko ` ? y m` sufosgöa {`a} hgvorko. Osto oeonpmb ab nuostr` quo m` prbpgoh`h oauafg`h` oa d) sömb v`mo fu`ahb m` sufosgöa ho mbs nöhumbs fbavorko ` 9
4
Nöhumb G - _agh`h 8
N`tonàtgf` H
♣ Vufosgbaos ho cuafgbaos V`donbs y` quo ua` sufosgöa os ua` cuafgöa fuyb hbngagb os om fbaeuatb ho aõnorbs a`tur`mos A , sg ` f`h` a`tur`m a mo l`fonbs fbrrospbahor ua` cuafgöa c a(z) , hofgnbs quo so l` hocgaghb ua` sufosgöa ho cuafgbaos y m` `abt`nbs {c a(z)}. A`tur`mnoato m`s cuafgbaos c a toahràa ua hbngagb H, hbaho so nbvorà m` v`rg`dmo z Oeonpmbs a
4
Vg c a(z) > z , mbs tros prgnorbs tçrngabs ho ost` sufosgöa sba m`s cuafgbaos c 0(z) > z, c 4(z) > z , c 6(z) > z6 , t`ndgça pbhonbs osfrgdgr {z , z4 , z6, z8 , ....} b sgnpmonoato `abt`ahb {za} . Oa osto f`sb om hbngagb ho m`s cuafgbaos sba tbhbs mbs fbnpmoebs. Os gnpbrt`ato bdsorv`r quo sg roonpm`z`nbs m` v`rg`dmo z pbr ua fbnpmoeb cgeb z9 , bdtoaonbs ua` sufosgöa aunçrgf` fbnpmoe` {z9a} . Vg tbn`nbs z9 > g bdtoaonbs m` sufosgöa aunçrgf` {ga} : sg z9 > 0/4 ogω bdtoaonbs m` sufosgöa aunçrgf` { (0/4 ogω )a } ♣
Fbavorkoafg` ho ua` sufosgöa ho cuafgbaos (t`ndgça mm`n`h` fbavorkoafg` puatu`m)
Y`r` ostuhg`r m` fbavorkoafg` ho ua` sufosgöa ho cuafgbaos {c a(z)} t`ndgça hodonbs f`mfum`r om mîngto ho su tçrngab koaor`m, os hofgr f`mfum`r mîn c a(z) y puoho sufohor quo p`r` `mkuabs a↔ ∑
v`mbros ho z hgflb mîngto oxgst` y p`r` btrbs v`mbros ho z ab oxgst`. Vg om mîngto `atorgbr sömb oxgsto p`r` mbs fbnpmoebs z ho ua fbaeuatb H0 fbatoaghb b gku`m `m hbngagb H ho m`s cuafgbaos, hofgnbs quo m` sufosgöa {c a(z)} fbavorko oa H0, y quo H0 os m` rokgöa ho fbavorkoafg` ho m` sufosgöa, oa f`ndgb sg mîn c a(z) ab oxgsto p`r` mbs rost`atos a↔ ∑
fbnpmoebs, so hgfo quo m` sufosgöa hgvorko p`r` mbs
z quo ab portoaofoa ` H0.
Os gnpbrt`ato rof`mf`r quo fu`ahb `cgrn`nbs quo ua` sufosgöa ho cuafgbaos fbavorko p`r` mbs z ho ua fbaeuatb H0 , quoronbs hofgr quo sg so roonpm`z` z pbr fu`mqugor omonoatb ho H0 so bdtgoao ua` sufosgöa aunçrgf` fbavorkoato, os hofgr m` sufosgöa fbavorko oa tbhbs mbs puatbs ho H0 y pbr ommb so suomo hofgr quo m` sufosgöa fbavorko puatu`mnoato p`r` mbs z hom fbaeuatb H0. ♣
Hocgagfgöa cbrn`m 5 Vg mîn c a(z) > c(z) p`r` mbs z portoaofgoatos ` ua fbaeuatb H 0 , hofgnbs a↔ ∑
quo m` sufosgöa {c a (z)} sgkagcgf` quo5
fbavorko puatu`mnoato (b fbavorko) ` c(z) p`r` mbs z ho H0 y
h`hb fu`mqugor aõnorb pbsgtgvb ο, os pbsgdmo oafbatr`r ua aõnorb A (quo hopoaho oa koaor`m ho ο y ho z) t`m quo |c a (z)- c(z) | = ο , p`r` tbhb a 1 A y p`r` tbhb z hom fbaeuatb H0 Oeonpmb 6
Nöhumb G - _agh`h 8
N`tonàtgf` H
0- Vo qugoro `vorgku`r sg m` sufosgöa 0 4 0 4
0 8 0 a 8
{za} fbavorko p`r` mbs v`mbros z0> 0 + 4g , z4 > g ,
g a 4
a
os hofgr quoronbs `vorgku`r sg m`s sufosgbaos aunçrgf`s (0 + 4g) , za6 > + g y zg 8 > a ( ) , g , ( + g ) , ( 4 ) fbavorkoa, sgnpmonoato l`y quo f`mfum`r om mîngto p`r` a ↔ ∑ ho f`h` ua` ho omm`s y mb hoe`nbs fbnb oeorfgfgb. ²p`r` quç btrbs v`mbros ho z fbavorko2, ²p`r` quç btrbs v`mbros ho z hgvorko2 Y`r` rospbahor ost`s prokuat`s hodonbs tr`d`e`r fba m` sufosgöa ho cuafgbaos t`m fu`m cuo h`h` y p`r` f`mfum`r om mîngto os fbavoagoato oxpros`r `m fbnpmoeb z oa cbrn` pbm`r, os hofgr tbn`r z > r o gμ , y fbnoaz`r `vorgku`ahb sg m` sufosgöa ho mbs nöhumbs fbavorko5 9 sg r = 0
mîn |za |> mîn ra > 0 a↔ ∑
a↔ ∑
sg r > 0 ∑ sg r 1 0
Bdsorv`nbs quo5 sg r > | z | = 0 , os hofgr sg z portoaofo `m gatorgbr hom fîrfumb ho r`hgb 0, m` sufosgöa ho mbs a nöhumbs {|z |} fbavorko ` 9 , pbr mb t`atb, us`ahb `) ho m` `ftgvgh`h 0, pbhonbs hofgr quo m` a sufosgöa sga mbs nöhumbs {z } t`ndgça fbavorko ` 9 sg |z | = 0
sg r > | z | > 0, os hofgr sg z portoaofo ` m` fgrfuacoroafg` ho r`hgb 0, m` sufosgöa {|za |} fbavorko ` 0 , porb ostb ab sgrvo p`r` rospbahor sbdro m` fbavorkoafg` ho {za } (p`rto f) ho m` `ftgvgh`h 0) . Y`r` rospbahor oa osto f`sb l`y quo f`mfum`r
sg μ > 9 0 mîn 0.o gaμ > mîn (fbs(aμ) + gsoa(aμ) > a↔ ∑ a↔∑ = μ = ω ab oxgsto sg 9 4 Ybr mb t`atb , sbdro mbs puatbs ho m` fgrfuacoroafg` |z| > 0, m` sufosgöa hgvorko s`mvb oa z > o9g > 0 quo fbavorko ` 0
sg r > | z | 1 0 , os hofgr sg z portoaofo `m oxtorgbr ho m` fgrfuacoroafg` ho r`hgb 0, m` sufosgöa ho mbs nöhumbs hgvorko , y sg mbs nöhumbs tgoahoa ` ∑ , m` sufosgöa ab puoho sor fbavorkoato.
9 sg | z | = 0 Fbafmusgöa 5 M` sufosgöa {za} fbavorko ` m` cuafgöa c(z) > 0 sg z > 0 p`r` mbs z hom fbaeuatb H > {z / | z |= 0 b z > 0}
0
4- Os gnpbrt`ato bdsorv`r quo m` sufosgöa `atorgbr, sg dgoa fbavorko oa mbs puatbs gahgf`hbs ab mb l`fo fba gku`m r`pghoz puos
Vg fbasghor`nb fbasghor`nbss z > 9, oatbafos m` hgcoroafg` |c a (9)- c(9) | > | 9 - 9 | > 9 y pbr mb t`atb os noabr quo fu`mqugor aõnorb pbsgtgvb ο p`r` fu`mqugor a quo so fbasghoro. 8
Nöhumb G - _agh`h 8
N`tonàtgf` H
a
Vg fbasghor`nbs z > 0, oatbafos m` hgcoroafg` |c a (0)- c(0) | > | 0 - 0 | > 9 y pbr mb t`atb os noabr quo fu`mqugor aõnorb pbsgtgvb ο p`r` fu`mqugor a quo so fbasghoro.
Vg fbasghor`nbs ua fbnpmoeb z ≩ 9 t`m quo
| z | = 0 oatbafos m` hgcoroafg`
|c a (z)- c(z) | > |z a - 9 | > | z |a = ο
, fbnb quoronbs `vorgku`r p`r` quç v`mbros ho a so funpmo hgfl` hosgku`mh`h `pmgf`nbs mbk`rgtnb ` `ndbs ngondrb y bdtoaonbs a ma |z | = ma ο ma ο (bdsorv`r quo oa om õmtgnb p`sb so f`ndgö m` hosgku`mh`h puos hgvghgnbs `ndbs ngondrbs ⇔ a 1 ma | z | ma |z| , quo os aok`tgvb pbr sor | z |= 0) . ma ο os om quo oa m` hocgagfgöa so hoabngaö Om aõnorb
pbr
ma | z |
A y vonbs quo hopoaho ho ο y ho z.
Y`r` fm`rgcgf`r fbasghoronbs m`s sgkugoatos sgtu`fgbaos5 Vg |z| > 0/4 y ο > 0/099 ⇔ a 1 ma(0/099)/ma(0/4) > 3,38..... , pbr mb t`atb ` p`rtgr hom tçrngab ; ho m` sufosgöa, m` hgcoroafg` oatro oatro c a (z) y c(z) os noabr quo ο > 0/099 Vg |z| > 7/09 y ο > 0/099 ⇔ a 1 ma(0/099)/ma(7/09) > 86,;9..... , pbr mb t`atb ` p`rtgr hom tçrngab 88 ho m` sufosgöa, m` hgcoroafg` oatro c a (z) y c(z) os noabr quo ο > 0/099 . Ovghoatonoato m` sufosgöa fbavorko ` forb ho ua` n`aor` nuflb nàs moat` p`r` mbs fbnpmoebs quo vorgcgf`a |z| > 7/09 quo p`r` mbs fbnpmoebs quo funpmoa |z| > 0/4
• Oeorfgfgbs 0- L`mm`r y kr`cgf`r mbs fgafb prgnorbs tçrngabs ho m`s sgkugoatos sufosgbaos y `a`mgz`r su fbavorkoafg`.
ga `) z a > a
d)
z a > (0 ∔ g ) a 4a
f)
za >
0 a∔g
∔
ga a+0
4- `) H`h` m` sufosgöa c a(z) > |z | , eustgcgf`r quo fbavorko puatu`mnoato oa | z | ≨ 0 ` 9 sg | z |= 0 y hgvorko oa |z | 1 0 c ( z ) > 0 sg | z |> 0 d) Fbnprbd`r quo m` sufosgöa {oaz} fbavorko puatu`mnoato oa om fbaeuatb {z / To(z) = 9} ` m` cuafgöa k(z) > 9
6- @vorgku`r p`r` quç v`mbros ho cuafgbaos
z fbavorkoa puatu`mnoato m`s sgkugoatos sufosgbaos ho
?
Nöhumb G - _agh`h 8
N`tonàtgf` H
`)
ga a+ | z |
d)
a + g az
f)
o
-gaz
h)
o ga To( z ) a
o)
o a To( z ) a
♣ Fbavorkoafg` uagcbrno ho ua` sufosgöa ho cuafgbaos Vg s`donbs quo m` sufosgöa {c a(z)} fbavorko puatu`mnoato ` c(z) p`r` mbs z ho H0 , os hofgr sg s`donbs quo mîn c a(z) > c(z) p`r` mbs z ho ua fbaeuatb H0 , oatbafos pbhonbs `cgrn`r quo a↔ ∑
h`hb fu`mqugor aõnorb pbsgtgvb ο, os pbsgdmo oafbatr`r ua aõnorb A (quo hopoaho oa koaor`m ho ο y ho z) t`m quo |c a (z)- c(z) | = ο , p`r` tbhb a 1 A y p`r` tbhb z ho H0 . ²Vorà pbsgdmo oafbatr`r ua aõnorb A quo ab hopoah` ho z , t`m quo m` hgcoroafg` |c a (z)- c(z)| = ο p`r` tbhb a 1 A y p`r` tbhb z hom fbaeuatb H0 ö p`r` tbhb z ho ua fbaeuatb H4 fbatoaghb oa H02 Vg m` rospuost` ` osto gatorrbk`ato os `cgrn`tgv`, so hgfo quo m` sufosgöa uagcbrnonoato oa om fbaeuatb H4 ⊃ H0 ♣
{c a(z)} fbavorko
Hocgagfgöa cbrn`m 5 Hofgnbs quo m` sufosgöa {c a(z)} fbavorko uagcbrnonoato ` c(z) p`r` mbs z ho H4 sg 5 h`hb fu`mqugor aõnorb pbsgtgvb ο, os pbsgdmo oafbatr`r ua aõnorb A (quo hopoaho sömb ho ο) t`m quo |c a (z)- c(z) | = ο , p`r` tbhb a 1 A y p`r` tbhb z hom fbaeuatb H4
Oeonpmb
W` lonbs `a`mgz`hb m` fbavorkoafg` ho m` sufosgöa {za} y s`donbs quo fbavorko puatu`mnoato ` 9 sg | z | = 0 p`r` mbs z hom fbaeuatb H > {z / | z |= 0 b z > 0}, ²m` m` cuafgöa c(z) > 0 sg z > 0 fbavorkoafg` sorà uagcbrno oa om fîrfumb
| z | ≨ 6/8 2
Y`r` rospbahor `a`mgz`nbs m` hgcoroafg` y fbnb abs hgfoa quo sg oxgkgnbs quo
|c a (z)- c(z) | > |z a - 9 | > | z | a ,
| z | ≨ 6/8 , pbhonbs osfrgdgr |c a (z)- c(z) | > |z a - 9 | > | z | a ≨ (6/8)a ,
|c a (z)- c(z) | ≨ (6/8)a = ο ,
pbhonbs hospoe`r a `pmgf`ahb mbk`rgtnb ` `ndbs ngondrbs bdtoagoahb a ma (6/8 ) = ma ο , ho ma ο , sg hoabnga`nbs A ` osto aõnorb , vonbs quo ab hopoaho ho z y pbr mb hbaho a 1
ma( 6 / 8)
t`atb m` sufosgöa fbavorko uagcbrnonoato oa | z | ≨ 6/8 .
ma(0 / 099) Bdsorv`r quo sg ο > 0/099 , oatbafos A > ma(6 / 8) > 03,99;.... , pbr mb t`atb p`r` tbhb a 1 03 pbhonbs `cgrn`r quo m`s hgcoroafg`s |c a (z)- c(z) | ≨ 0/099 , p`r` mbs z quo vorgcgf`a | z | ≨ 6/8 . 3
Nöhumb G - _agh`h 8
N`tonàtgf` H
_a r`zba`ngoatb sgngm`r porngto honbstr`r quo ost` sufosgöa fbavorko uagcbrnonoato p`r` | z | ≨ ` , fba ` = 0 puos oa osto f`sb so bdtgoao quo A > ma ο / ma ` y rosumt` ovghoato quo ` ab puoho tbn`r om v`mbr 0.
4- Vorgos
H`h` ua` sufosgöa aunçrgf`
{`a}a≯0 , m` oxprosgöa
∑
` a so hoabnga` sorgo `sbfg`h` ` m` ∐ a 0 >
sufosgöa b sgnpmonoato sorgo. ²Fuàm os om sgkagcgf`hb ho m` oxprosgöa `atorgbr2, ²s`donbs sun`r gacgagtbs aõnorbs2 Os gatoros`ato bdsorv`r quo sömb s`donbs sun`r hbs aõnorbs, pbrquo sg aofosgt`nbs sun`r tros , prgnorb sun`nbs hbs ho ommbs y `m rosumt`hb mo sun`nbs om btrb. ²Fuàm os oatbafos om sgkagcgf`hb ho os` sun` gacgagt` quo lonbs mm`n`hb sorgo2 Mbs p`sbs quo sgkuoa rospbahoràa osto gatorrbk`ato. Fbnb s`donbs sun`r ua aõnorb cgagtb ho tçrngabs , ost`nbs oa fbahgfgbaos ho f`mfum`r m`s sgkugoatos sun`s5
V0 > `0 V4 > `0 + `4 > V0 + `4 V6 > `0 + `4 + `6 > V4 + `6 ............................. Va > `0 + `4 + `6 + ............+ `a > Va-0 + `a ............................................ .................... ................................................. ...........................
y ho osto nbhb koaor`nbs ua` auov` sufosgöa
p`rfg`mos b sorgo y so gahgf`
{Va} ` m` quo so hoabnga` sufosgöa ho sun`s
∑
`a ∐ a 0 >
♣ Fbavorkoafg` ho ua` sorgo aunçrgf` ∑
Vg
` a os ua` sorgo aunçrgf` y m` sufosgöa ho sun`s p`rfg`mos {Va} fbavorko , os hofgr sg oxgsto ∐ a 0 >
mîn V a >V, hofgnbs quo m` sorgo fbavorko y quo V os m` sun` ho m` sorgo, `abt`nbs oa osto a↔ ∑
∑
f`sb
` a > V . Vg m` sufosgöa {Va} hgvorko, hofgnbs quo m` sorgo hgvorko. ∐ a 0 >
@lbr` fbnproahonbs fuàm os om sgkagcgf`hb ho sun`r mbs gacgagtbs tçrngabs ho ua` sorgo, y` quo
sg m` sorgo fbavorko toaonbs quo a
∑
a 0 ` ∐ >
a
j a↔ ∑ a↔ ∑ ↔∑ (`0 + `4 + ......+ `a ) > mîn > V > mîn V a > amîn j >0 ` ∐
;
Nöhumb G - _agh`h 8
N`tonàtgf` H
∑
Ybr mb t`atb fu`ahb hofgnbs quo m` sorgo fbavorko o gahgf`nbs
`a > V , ∐ a 0
oa ro`mgh`h sgkagcgf`
>
quo sun`nbs a aõnorbs y muokb l`fonbs toahor a ` gacgagtb.
∃ @ftgvgh`h 45 ∑
Eustgcgf`r quo
∐ a 0
sî (d a + gf a ) fbavorko y tgoao sun` D + g F sî y sömb sî
∑
d a fbavorko ` D y ∐ a 0 >
>
∑
f a fbavorko ` F ∐ a 0
@yuh`5 honbstr`r quo sg Va os m` sun` p`rfg`m ho m` prgnor` sorgo oatbafos
Va
>
> Da + g Fa hbaho Da y Fa sba m`s sun`s p`rfg`mos ho m` m ` btr`s hbs rospoftgv`noato.
♣
Fbavorkoafg` ho ua` sorgo ho cuafgbaos ( t`ndgça mm`n`h` fbavorkoafg` puatu`m) ∑
Hofgnbs quo ua` sorgo ho cuafgbaos
c a ( z ) fbavorko puatu`mnoato oa ua fbaeuatb H0 sg m` ∐ a 0 >
sufosgöa ho sun`s p`rfg`mos {Va(z)} fbavorko puatu`mnoato ` Y`r` l`mm`r om fbaeuatb
V(z) p`r` mbs z hom fbaeuatb H0
H0, l`y quo `vorgku`r p`r` quç v`mbros ho z oxgsto mîn V a (z) y om a↔ ∑
fbaeuatb ho tbhbs ommbs fbastgtuyo om fbaeuatb H0 , hoabnga`hb rokgöa ho fbavorkoafg` ho m` sorgo . Vg V(z) os om rosumt`hb ho hgflb mîngto , hofgnbs quo V(z) os m` sun` ho m` sorgo y `abt`nbs ∑
c a ( z ) > V(z) , p`r` mbs z hom fbaeuatb H0 ∐ a 0 >
∑
♣
a ` p`r` mbs Hocgagfgöa cbrn`m 5 Hofgnbs quo m` sorgo ∐ a >0 c ( z ) fbavorko puatu`mnoato V(z) z ho H0 sg 5 h`hb fu`mqugor aõnorb pbsgtgvb ο, os pbsgdmo oafbatr`r ua aõnorb A (quo hopoaho oa koaor`m ho ο y z ) t`m quo |Va (z)- V(z) | = ο , p`r` tbhb a 1 A y p`r` tbhb z hom fbaeuatb H0
Y`r` fm`rgcgf`r m` hocgagfgöa ho sorgo fbavorkoato, `a`mgz`nbs ` fbatgau`fgöa ua` sorgo quo utgmgz`ronbs nuflb oa m`s fm`sos sgkugoatos y quo so hoabnga` sorgo kobnçtrgf`.
♣ Vorgo kobnçtrgf`
_a` sorgo os kobnçtrgf`, sg tgoao m` cbrn`
∑
∐ ` 9 r a > `9 + `9 r + `9 r4 + `9 r6 +............. a>9
<
Nöhumb G - _agh`h 8
N`tonàtgf` H
bdsorv`r quo f`h` tçrngab os gku`m `m `atorgbr numtgpmgf`hb pbr ua c`ftbr cgeb, oa osto f`sb om c`ftbr os r , quo so hoabnga` r`zöa, y ua prgnor tçrngab, quo oa osto f`sb lonbs hoabnga`hb `9
Oeonpmbs
`) _a` sorgo kobnçtrgf` ho prgnor tçrngab 4g y r`zöa
4g + 4g o-0 + ωg + 4g (o-0 + ωg )4 + 4g (o-0 + ωg )6 +........>
o-0 + ωg tgoao m` cbrn` ∑
∐ a 9 >
d) M` sorgo ho cuafgbaos
∑
4g o a(-0+ ωg) > ∐ 4g (-0) a o -a a>9
∑
4(-g) 6a (z - 6g) 4a > 4 (- g)6 (z -6g)4 + 4 (- g)3 (z -6g)8 + ......... ∐ a 0 >
sorgo kobnçtrgf` fba prgnor tçrngab
os ua`
4 (- g)6 (z -6g)4 y r`zöa (-g)6 (z- 6g)4
∃ @ftgvgh`h 65 Eustgcgf`r m` sgkugoato oqugv`moafg` 5 ∑
fa ∐ a 9
os ua` sorgo kobnçtrgf` ⇘ (∉a) om fbfgoato fa + 0 / fa ab hopoaho ho a y su v`mbr os gku`m
>
` m` r`zöa .
∃ @ftgvgh`h 85 Fbasghor`ahb quo
Va > `9 + ` 9 r + `9 r4 + .....+ `9 ra-0 os m` sun` p`rfg`m ho m` sorgo kobnçtrgf`
∑
` 9 r a , honbstr`r quo 5 ∐ a 9 >
`) Vg r > 0 ⇔ Va > a. `9 ` 9 (0 ∔ r a ) d) Vg r ≩ 0 ⇔ V a > (`yuh`5 f`mfum`r m` hgcoroafg` 0∔r f) Vg | r | ≯ 0 ⇔ {Va} hgvorko , h) Vg
| r | = 0 ⇔ m` sorgo kobnçtrgf` fbavorko y su sun` os V >
Oeonpmb ∑
(∔ 0)a (6z ∔ 4)6a+ 4
Va - r Va y hospoe`r Va ) `9 0∔r
Vg quoronbs s`dor sg m` sorgo
∐ a 0
os kobnçtrgf` ro`mgz`nbs om fbfgoato oatro ua
< 4a
>
tçrngab y su `atorgbr bdtoagoahb oa osto f`sb5
(∔ 0)a +0 (6z ∔ 4)6( a+0)+ 4 < 4( a +0)
(∔ 0)a (6z ∔ 4)6a + 4 < 4a
(6z ∔ 4)6 , fbnb osto fbfgoato ab hopoaho ho a, m` >∔
(6z ∔ 4)6 ∔ V( z ) > 0∔ r ∔ 0 + , lonbs toaghb oa fuoat` quo `9 4 6 + ∔ < 38 ( 6 z 4 )
os om prgnor tçrngab ho m` sorgo, quo oa osto f`sb so bdtgoao roonpm`z`ahb a pbr 0
• Oeorfgfgbs 8- Hotornga`r, dusf`ahb provg`noato m` sufosgöa ho sun`s p`rfg`mos, p`r` quç v`mbros ho z fbavorkoa m`s sgkugoatos sorgos ho cuafgbaos (bdsorv`r quo m`s hbs õmtgn`s sba kobnçtrgf`s). Oa f`sb ho fbavorkoafg`, gahgf`r su sun`.
z z `) ∐ ∔ + a a 0 a >0 ∑
∑
d)
∐ a 0 >
4a
4 a x 4a ∔0 f) ∐ a 6 a >0
4 z ∔ g (∔ 0) 8 a
∑
?- @a`mgz`ahb om fbnpbrt`ngoatb ho m` sufosgöa ho sun`s p`rfg`mos, fbnprbd`r quo5 ∑
`)
(z ∐ a 9 > >
a
a +0
∔z
0 sg | z | = 0 ) >
z a z a ∔0 z+? d) ∐ a +0 + a > sg | z | = ? 4? ? z ∔ ? ? a 0 > ∑
9 sg z > 0
@ fbatgau`fgöa, y ` nbhb ho rop`sb, rop`sb, so oauafg`a mbs frgtorgbs nàs ggnpbrt`atos npbrt`atos quo porngtoa ostuhg`r ostuhg`r m` fbavorkoafg` b hgvorkoafg` ho ua` sorgo, tbhbs ommbs so l`a vgstb y utgmgz`hb p`r` sorgos ro`mos y sgkuoa v`mgoahb p`r` sorgos fbnpmoe`s fba `mkuabs rof`uhbs.
Fbahgfgöa aofos`rg` ho fbavorkoafg` 5 Vg
∑
` a fbavorko ↔ mîn ` a > 9 ∐ a a 0 >
↔∑
∑
Fbahgfgöa sucgfgoato ho hgvorkoafg` 5 Vg mîn ` a ≩ 9 b mîn ` a ab oxgsto ↔ ∐ ` a hgvorko a↔ ∑
a↔∑
Bdsorv`fgöa 5 h`h`
∑
` a , sg ∐ a 0 >
a >0
hgvorkoato oato mîn ` a > 9 ab so puoho hofgr sg m` sorgo os fbavorkoato b hgvork a ↔∑
09
Nöhumb G - _agh`h 8
N`tonàtgf` H
Xobron`5 Vg
∑
∑
a >0
a >0
∐ | ` a | fbavorko ↔ ∐ ` a fbavorko
∑
∑
>
>
| fj | fbavorko, so hgfo quo m` sorgo ∐ fj os `dsbmut`noato fbavorkoato . ∐ j 0 j 0
♣ Vg
Frgtorgb ho fbnp`r`fgöa5 ∑
`) Vg
|fa | ≨ |da | y
∐ a 0
da
∑
fbavorko ↔
>
∑
d) Vg |fa | ≯ |`a |
y
∐ `a
∐ a 0
fa
fbavorko
>
hgvorko ↔
a >0
∑
f a hgvorko ∐ a 0 >
∑
Frgtorgb ho H‗@m`ndort b hom fbfgoato5
H`h` m` sorgo
fj , sg ∐ j 0 >
`) sg
∑
∐ a 0
M = 0 ↔
|f | mîn a +0 > M oatbafos5 a ↔∑ | f | a
fa fbavorko
>
∑
d) sg f) sg
0 = M ≨ ∑ ↔ mîn f a ≩ 9 ↔ ∐ f a hgvorko a ↔∑
a >0
M > 0 om frgtorgb ab hofgho, puoho sor quo m` sorgo so` fbavorkoato b hgvorkoato. ∑
Frgtorgb ho F`ufly b ho m` r`îz5 H`h` m` sorgo ∐ fj , sg mîn a | f a | > M oatbafos5 j >0
∑
`) sg
∐ a 0
M = 0 ↔
a↔∑
fa fbavorko
>
∑
d) sg f) sg
0 = M ≨ ∑ ↔ mîn f a ≩ 9 ↔ ∐ f a hgvorko a ↔∑
a >0
M > 0 om frgtorgb ab hofgho, puoho sor quo m` sorgo so` fbavorkoato b hgvorkoato
• Oeorfgfgbs 3- Ostuhg`r m` fbavorkoafg` `dsbmut` ho m`s sgkugoatos sorgos aunçrgf`s utgmgz`ahb ua frgtorgb `hofu`hb. ∑
`)
0
∑
d)
a(4 + g )a
∑
f)
a
∐ a 9
∐ a 0
(0 + ga )4
>
∐ a 0
4a
>
>
;- @vorgku`r utgmgz`ahb `mkõa frgtorgb p`r` quç v`mbros ho
(4g )a z fbavorkoa `dsbmut`noato m`s
sgkugoatos sorgos ho cuafgbaos5
00
Nöhumb G - _agh`h 8
N`tonàtgf` H
4a
4z `) ∐ a a >0 ∑
∑
d)
ao ∐ a 9
az
( ∔0a )a f) ∐ a ( ) + z g a >0 ∑
>
(z + 4)4a a ∐ ( ) 8 a 0 + a>9 ∑
h)
♣ Fbavorkoafg` uagcbrno ho sorgos ho cuafgbaos ∑
Vg sorgo ho cuafgbaos
c a ( z ) fbavorko puatu`mnoato ` ua` cuafgöa V(z) p`r` mbs z ho ua ∐ a 0 >
fbaeuatb H0 , hofgnbs quo m` sorgo fbavorko uagcbrnonoato oa ua fbaeuatb H4 ⊃ H0 sg m` sufosgöa ho sun`s p`rfg`mos {Va(z)} fbavorko uagcbrnonoato ` V(z) p`r` mbs z hom fbaeuatb H4 . ♣
Hocgagfgöa cbrn`m 5 Hofgnbs quo m` sorgo
∑
c a ( z ) fbavorko uagcbrnonoato ` V(z) p`r` ∐ a 0 >
mbs z ho H4 sg 5 h`hb fu`mqugor aõnorb pbsgtgvb ο, os pbsgdmo oafbatr`r ua aõnorb A (quo hopoaho sömb ho ο ) t`m quo |Va (z)- V(z) | = ο , p`r` tbhb a 1 A y p`r` tbhb z hom fbaeuatb
H4 Oeonpmb
0- Vg quoronbs `vorgku`r p`r` quç v`mbros ho z fbavorko uagcbrnonoato m` sorgo 4
6
4
z + (z - z) + (z - z ) +....... > z +
∑
(z a 0 ∔ z a ) ∐ a 0 +
>
fbnoaz`nbs dusf`ahb su sufosgöa ho sun`s p`rfg`mos
V0(z) > z V4(z) > z + (z4 - z) > z4 V6(z) > z + (z4 - z) + (z6 - z4) > z6 ............................................. a
Va(z)
>z
Ybr mb t`atb m` sufosgöa ho sun`s p`rfg`mos os Va(z) > za , quo y` lonbs `a`mgz`hb y s`donbs quo fbavorko uagcbrnonoato oa om fîrfumb |z|≨ ` , fba ` = 0, pbr mb t`atb m` sorgo h`h` fbavorko uagcbrnonoato oa fu`mqugor fîrfumb foatr`hb oa om brgkoa fba r`hgb noabr quo uab. Ab sgonpro os t`a soafgmmb l`mm`r m` sufosgöa ho sun`s p`rfg`mos p`r` muokb f`mfum`rmo om mîngto y `vorgku`r sg oxgsto ua A, quo hopoah` sömb ho ο , p`r` rospbahor sbdro m` fbavorkoafg` uagcbrno, pbr ommb os gnpbrt`ato hgspbaor ho `mkõa frgtorgb quo rospbah` y om sgkugoato suomo sor utgmîsgnb.
04
Nöhumb G - _agh`h 8
N`tonàtgf` H
Α Frgtorgb N ho [ogorst`ss ∑
Vg m` sorgo aunçrgf`
N tgoao tçrngabs ro`mos pbsgtgvbs y os fbavorkoato y f`h` tçrngab ho a
∐ m` sufosgöa ho cuafgbaos {c a(z)} a>0
∑
sorgo
c a (z) ∐ a0
vorgcgf`
| c a(z)| ≨ N a p`r` mbs z ho ua fbaeuatb H* oatbafos m`
fbavorko uagcbrnonoato p`r` mbs z hom fbaeuatb H*.
>
Oeonpmbs
oaz Vg quoronbs `vorgku`r p`r` quç v`mbros ho z fbavorko uagcbrnonoato m` sorgo ∐ 4 us`ahb om a>0 a ∑
frgtorgb `atorgbr, fbasghor`nbs om nöhumb ho f`h` tçrngab fbnb so gahgf` ` fbatgau`fgöa
oaz oax oa` a4 > a4 (≨0) a4 hbaho oa (0) lonbs supuostb quo x ≨ ` Bdsorvonbs quo om õmtgnb fbfgoato ab hopoaho z, y sg mb mm`n`nbs | c a(z)| ≨ Na p`r` mbs z quo vorgcgquoa To(z) > x ≨ `
Na , pbhonbs `cgrn`r quo
oa` Fba mbs aõnorbs Na cbrn`nbs m` sorgo aunçrgf` ∐ 4 y `a`mgz`nbs su fbavorkoafg` us`ahb a>0 a om frgtorgb hom fbfgoato, hoe`nbs fbnb oeorfgfgb vorgcgf`r quo M > o` , pbr mb t`atb ost` sorgo ` fbavorko sg M > o = 0 , ho hbaho so hosproaho quo ` hodo sor aok`tgvb. Ybr mb t`atb m` sorgo ∑ oa` [ogorst`ss aunçrgf` ∐ 4 fbavorko sg ` = 9 y `pmgf`ahb om frgtorgb ho [ogorst`ss a>0 a 9 pbhonbs `cgrn`r quo m` sorgo h`h` fbavorko uagcbrnonoato sg To(z) ≨ ` = 9 ∑
• Oeorfgfgbs
oatbafos v`moa m`s sgkugoatos prbpgoh`hos5
⇔
`) Vg m`s cuafgbaos c a(z) sba fbatgau`s oa
H
V(z) os fbatgau` oa H 06
Nöhumb G - _agh`h 8
N`tonàtgf` H
d) Vg F os ua` furv` su`vo pbr tr`nbs fbatoagh` oa H ⇔ m` gatokr`m sbdro F ho m` sorgo os gku`m ` ∑ ∑ c (z) hz > c (z) hz F a a>0 a a>0 ∐ ∐ ∪
(
m` sorgo ho m`s gatokr`mos sbdro F , os hofgr F
)
H ∪⇔ V(z) os `a`mîtgf` oa H y m` horgv`h` ho m` sorgo ∑ h h ∑ os gku`m m` sorgo ho m`s horgv`h`s, os hofgr ∐ c a (z) > ∐ (c a (z)) hz a>0 hz a>0 h) Vg k(z) os ua` cuafgöa `fbt`h` oa H , os hofgr |k(z)| ≨ J p`r` mbs z ho H ⇔ f) Vg m`s cuafgbaos c a(z) sba `a`mîtgf`s oa
∑
k(z)c a (z) ∐ a 0
fbavorko uagcbrnonoato oa H y su sun` os k(z).
V(z)
>
♣ Vorgos ho pbtoafg`s Pugzàs m`s sorgos nàs gnpbrt`atos sba m`s
sorgos ho pbtoafg`s quo tgoaoa m` cbrn`
∑
f a (z ∔ z 9 ) ∐ a 9
a
> f9 + f0 (z - z9) + f4 (z - z9)4 + f6 (z - z9)6 +............
>
Mbs aõnorbs fa sba fbnpmoebs quo ab hopoahoa ho m` v`rg`dmo z y so hoabnga`a m` sorgo.
fbocgfgoatos ho
Os gnpbrt`ato bdsorv`r quo ost`s sorgos sba sorgos ho cuafgbaos hbaho om tçrngab koaor`m tgoao m` a cbrn` c a(z) > fa (z - z9) , pbr mb t`atb su sufosgöa ho sun`s p`rfg`mos os ua` sufosgöa ho cuafgbaos y pbr ommb m` sorgo puoho fbavorkor p`r` `mkuabs v`mbros ho z y hgvorkgr p`r` btrbs. ² Y`r` quç v`mbros ho z m` sorgo fbavorko2, ²Fönb oafbatr`r su rokgöa ho fbavorkoafg`2 Vg roonpm`z`nbs z pbr z9 , vonbs quo, s`mvb om prgnorb, tbhbs mbs tçrngabs ho m` sorgo sba gku`mos ` forb y pbr mb t`atb m` sorgo fbavorko oa z9 y su sun` os f9 . Y`r` oafbatr`r btrbs pbsgdmos v`mbros ho z p`r` mbs fu`mos m` sorgo fbavorko, so `pmgf` `mkõa ∑
frgtorgb ` m` sorgo ho mbs nöhumbs
| f a ( z ∔ z 9 ) a | ∐ a 9
, os hofgr so ostuhg` m` fbavorkoafg` `dsbmut`
>
ho m` sorgo Ybr oeonpmb, sg so `pmgf` om frgtorgb hom fbfgoato so bdtgoao
f a +0 | f a +0 ( z ∔ z 9 ) a +0 | z z mîn M > mîn > ∔ 9 a↔∑ a↔ ∑ | f ( z ∔ z ) a | f
a
a
9
0 8 48 6
@
Vg @ > 9 , oatbafos M > 9 y pbr sor M = 0, m` sorgo fbavorko `dsbmut`noato p`r` tbhb Vg @ > ∑ , zom> rosumt`hb homhomîngto hopoaho hom v`mbr ho z, . sg hgvorko , sg z9 s`donbs oatr`h` quo m` sorgo fbavorko
z
z ≩ z9 oatbafos M > ∑ y m` sorgo
08
Nöhumb G - _agh`h 8
N`tonàtgf` H
Vg @ ≩ 9 y @ ≩ ∑ , oatbafos M > |z - z9| @ , fbnb om frgtorgb hom fbfgoato oxgko quo M so` noabr quo 0 p`r` quo m` sorgo fbavore` , pbhonbs `cgrn`r quo m` sorgo ho pbtoafg`s fbavorko 9| = 0 / @ , pbr mb t`atb m` sorgo ho mbs nöhumbs `dsbmut`noato |z - z9`dgortb | @ = 0foatr`hb , os hofgroasg z9|z ho - zr`hgb fbavorko oa uasgfîrfumb 0/@.
Xoagoahb prosoato quo sg ua` sorgo fbavorko `dsbmut`noato oatbafos hgfl` sorgo fbavorko, pbhonbs oauafg`r om sgkugoato tobron`5
Α Xobron`5
Fbavorkoafg` Fbavorkoafg` ho sorgos ho pbtoafg`s5
Y`r` ua` sorgo ho pbtoafg`s
∑
f a (z ∔ z 9 ) a oxgstoa sbm`noato tros pbsgdgmgh`hos5 ∐ a 9 >
`) M` sorgo fbavorko õagf`noato fu`ahb
z > z9
d) M` sorgo fbavorko p`r` tbhb z f) Oxgsto ua aõnorb pbsgtgvb T t`m quo m` sorgo fbavorko oa
|z - z9| = T y hgvorko sg |z - z9| 1 T.
Om aõnorb T so hoabnga` r`hgb ho fbavorkoafg` ho m` sorgo. Vg m` sorgo fbavorko ∉z , so hgfo quo om r`hgb ho fbavorkoafg` os gacgagtb y `abt`nbs sg m` sorgo sömb fbavorko oa z9, so hgfo quo om r`hgb ho fbavorkoafg` os forb.
T > ∑ :
Oeonpmb
Vg quoronbs `vorgku`r p`r` quç v`mbros ho z fbavorko m` sorgo
∑
∐ a>9
4a + 0 (z ∔ g ) 4a pbhonbs a (4g)
`pmgf`r `mkõa frgtorgb. @ fbatgau`fgöa `pmgf`nbs om frgtorgb hom fbfgoato y so hoe` fbnb `ftgvgh`h m` eustgcgf`fgöa ho tbhbs mbs p`sbs `mkodr`gfbs quo so ro`mgz`a p`r` f`mfum`r om mîngto quo gatoros`.
f 4(a + 0) + 0 4 ( a +0 ) ∔ M > mîn a +0 > mîn ( ) z g a ↔∑ a ↔∑ f ( 4g ) a + 0 a Vg
4
z∔g 4a + 0 4a + 6 0 4 4a > ∔ > (z g) mîn z g a ↔∑ 4a + 0 4g 4 (4g) a
M = 0 ⇔ | z - g |4 = 4 ⇔ | z - g | = 4 , y sg M 1 0 ⇔ | z - g | 1 4
Ybr mb t`atb m` sorgo fbavorko oa om fîrfumb `dgortb
|z-g|=
4 y hgvorko oa | z - g | 1
4.
Vbdro mbs puatbs ho m` fgrfuacoroafg`
| z - g | > 4 ab pbhonbs `sokur`r sg fbavorko b hgvorko.
Vg oa f`ndgb hofghgnbs `pmgf`r om frgtorgb ho m` r`îz, m` sgtu`fgöa os m` sgkugoato5
0?
Nöhumb G - _agh`h 8
N`tonàtgf` H
4
a a z∔g 4a + 0 a 4a + 0 4a + 0 4 4a 4a > ∔ > ∔ > , M > mîn a (z g) mîn z g z g mîn a a↔ ∑ a ↔∑ a ↔∑ a 4 4 (4g) a 4g hbaho oa om õmtgnb p`sb so tuvb oa fuoat` quo mîn a 4a + 0 > 0 a ↔∑
Fbnb om frgtorgb ho m` r`îz oxgko, fbnb om frgtorgb hom fbfgoato, quo M so` noabr ` 0 p`r` quo m` sorgo fbavore`, ab l`fonbs nàs fbnoat`rgbs puos so bdsorv` quo m` fbafmusgöa os ghçatgf` ` m` y` bdtoagh`.
∃ @ftgvgh`h ?5 ∑
Vg m` sorgo ho pbtoafg`s
f a (z ∔ z 9 ) a ∐ a 9
fbavorko oa
|z - z9| = T , `vorgku`r p`r` quç v`mbros ho
>
z fbavorko m` sorgo ho pbtoafg`s aok`tgv`s
∑
f (z ∔ z ) ∔a a
a 9 -0 ∐ Gahgf`fgöa5 l`for om f`ndgb ho v`rg`dmo w > (z - z9) >
9
Α Xobron` 5 fbavorkoafg` uagcbrno ho m`s sorgos ho pbtoafg`s p btoafg`s ∑
Vg
f a (z ∔ z 9 ) a os ua` sorgo ho pbtoafg`s quo fbavorko `dsbmut`noato p`r` |z - z9 | = T ∐ a 9
fba
>
T≩ 9 ⇔ hgfl` sorgo fbavorko uagcbrnonoato oa |z - z9 | ≨ T0 = T Honbstr`fgöa Vo` z0 ua fbnpmoeb hom fîrfumb ∑ ho fbavorkoafg` ho m` sorgo, oatbafos m` sorgo aunçrgf` f a ( z 0 ∔ z 9 ) a (*) os fbavorkoato.
∐ a 9
T
z0
T0
z9
>
Vg fbasghoronbs tbhbs mbs fbnpmoebs z portoaofgoatos `m fîrfumb sbndro`hb ho m` cgkur` , os hofgr `quommbs quo vorgcgf`a | z - z9| ≨ | z0 - z9| oatbafos p`r` hgflbs fbnpmoebs so vorgcgf` quo |fa (z - z9)a| ≨ |fa (z0 - z 9)a| , toagoahb oa fuoat` quo m` sorgo (*) os fbavorkoato, pbr om frgtorgb ho ∑
[ogorst`ss pbhonbs `cgrn`r quo m` sorgo
f a (z ∔ z 9 ) a fbavorko ∐ a 9 >
uagcbrnonoato p`r` mbs
fbnpmoebs quo vorgcgf`a | z - z 9| ≨ | z 0 - z 9| , sg mm`n`nbs noabr quo T quoh` honbstr`hb mb quo protoahî`nbs.
T0 > | z0 - z9| , quo ovghoatonoato os
⊟ Bdsorv`fgöa 03
Nöhumb G - _agh`h 8
N`tonàtgf` H
∑
Fbnb `lbr` s`donbs quo m`s sorgos ho pbtoafg`s
uagcbrnonoa to p`r` f a (z ∔ z 9 ) a fbavorkoa uagcbrnonoato ∐ a 9 >
|z - z9 | ≨ T0 = T fba T r`hgb ho fbavorkoafg` , oatbafos m`s sorgos ho pbtoafg`s tgoaoa m`s ngsn`s prbpgoh`hos quo oauafg`nbs p`r` m`s sorgos quo fbavorkoa uagcbrnonoato, oa p`rtgfum`r pbhonbs `sokur`r quo p`r` mbs z hom fîrfumb |z - z9 | ≨ T0 = T v`moa m`s sgkugoatos gku`mh`hos5
z
z ∑ ∑ a a `) ∪ ∐ f a (z - z 9 ) hz > ∐ ∪ Zf a (z - z 9 ) ^ hz y pbr mb t`atb a >9 z 9 z 9 a>9
h ∑ d) ∐ f a (z ∔ z 9 ) a > hz a > 9
h Zf a ( z ∔ z 9 ) a ^ ∐ a > 9 hz ∑
f a (z - z 9 )a +0 ∪z c ( z) hz >∐ a 0 + a >9 9 z
y pbr mb t`atb c '(z) >
∑
∑
f a a(z ∔ z 9 ) a 0 ∐ a 9 ∔
>
Oeonpmb ∑
M` sorgo ho pbtoafg`s
z a os ua` sorgo kobnçtrgf` fba prgnor tçrngab ∐ a 9
`9 > 0 y r`zöa r > z ,
>
pbr mb t`atb fbavorko sg |
z | = 0 y oa hgflb fîrfumb `dgortb so vorgcgf` quo
0 0∔ z
∑
>
za ∐ a 9 >
Ybr tr`t`rso ho ua` sorgo ho pbtoafg`s pbhonbs gatokr`rm` y horgv`rm` tçrngab ` tçrngab y so bpor` fbnb so nuostr` ` fbatgau`fgöa. `) Gatokr`ahb `ndbs ngondrbs oatro 9 y z9 , fba | z9 | = 0, bdtoaonbs 5 z9
∪9
0
z9
0 ∔ z hz > ∪9
∑ ∑ a hz > ∐ a >9 z a>9 ∐
z9
∪9
z a +0 , z hz > ∐ a >9 a + 0 a
Fbnb m` prgngtgv` ho m` prgnor` gatokr`m os osfrgdgrso5
∑
- Ma (0 - z) , m` oxprosgöa `atorgbr puoho
∑ z 9 a +0 z 9 a +0 sg | z9 | = 0 ⇔ Ma(0 ∔ z 9 ) > ∔ ∐ ∔ Ma(0 ∔ z 9 ) + Ma0 > ∐ a >9 a + 0 a>9 a + 0 ∑
fbnb z9 os fu`mqugor fbnpmoeb hom fîrfumb | z | = 0 , pbhonbs roonpm`z`r z9 pbr z , bdtoagoahb5
z a +0 sg | z | = 0 Ma(0 ∔ z ) > ∔ ∐ a >9 a + 0 ∑
0;
Nöhumb G - _agh`h 8
N`tonàtgf` H
d)
Vg oa f`ndgb horgv`nbs `ndbs ngondrbs ho m` sorgo
0 0∔z
∑
>
za ∐ a 9
bdtoaonbs
>
h 0 > h ∑ z a > ∑ h ( z a ) > ∑ az a ∔0 > ∑ az a ∔0 ∐ ∐ ∐ ∐ hz hz 0 ∔ z hz a>9 a >0 a >9 a >9 ∑
(bdsorv`r quo oa om õmtgnb p`sb so f`ndgö
a > 9 pbr a > 0 puos om prgnor tçrngab ho m` sorgo ∐ az a ∔0 a>9
v`mo forb) ∑ 0 Ybr õmtgnb f`mfum`ahb m` horgv`h` ho 0 / (0 - z) bdtoaonbs5 > ∐ az a ∔0 sg | z | = 0 4 (0 ∔ z ) a>0
• Oeorfgfgbs ∑
7- H`h` m` sorgo
za
, `vorgku`r p`r` quo v`mbros ho z fbavorko y sg
V(z) os su sun` vorgcgf`r
∐ ya!V(9) > 0 , ²puoho `voatur`r fuàm os m` cuafgöa V(z)2 quo V'(z) > V(z) a >9
09- @vorgku`r p`r` quç v`mbros ho z fbavorko m` sgkugoato sorgo
∑
( ∔0) a z 4a y l`mm`r ua` sorgo ho ∐ a 9 >
pbtoafg`s ho z quo roprosoato ` m` cuafgöa c(z) > `rftk z o gahgf`r m` rokgöa ho v`mghoz.
♣ Bpor`fgbaos fba sorgos ho pbtoafg`s ∑
H`h`s hbs sorgos ho pbtoafg`s
` a (z ∔ z 9 ) ∐ a 9 >
a
∑
,
d a ( z ∔ z 9 ) a , abs prokuat`nbs sg hgfl`s ∐ a 9 >
sorgos so puohoa sun`r b numtgpmgf`r. Om sgkugoato tobron` abs rospbaho.
Α
Xobron` ∑
Vg
c(z) > ∐ ` a ( z ∔ z 9 ) oa |z - z9| = T0 a
k(z) >
y
a> 9
∑
d a ( z ∔ z 9 ) a oa ∐ a 9
|z - z9| = T4
>
y
T6 > nîa {T0 , T4} oatbafos5
`)
c(z) + k(z) > ∐ ` a ( z ∔ z 9 ) a + ∐ d a (z ∔ z 9 ) a >
∑
∑
∑
∐ (` a + d a )(z ∔ z 9 )a oa
|z - z9| = T6
a>9
a >9
∑
d)
a>9
∑
c(z) . k(z) > ∐ ` a ( z ∔ z 9 ) . ∐ d a ( z ∔ z 9 ) a
a >9
a
∑
>
a>9
h a ( z ∔ z 9 ) a oa |z - z9| = T6 , sgoahb ∐ a 9 >
h9 > `9 d9 , h0 > `9 d0 + `0 d9 , h4 > `9 d4 + `0 d0 + `4 d9 , .. , ha > `9 da+ `0 da-0 + ... + `a d9 0<
Nöhumb G - _agh`h 8
N`tonàtgf` H
Bdsorv`r quo t`atb m` sun` fbnb om prbhuftb ho hbs sorgos ho pbtoafg`s ho gatorsoffgöa ho mbs fîrfumbs ho fbavorkoafg` ho f`h` ua` ho omm`s.
(z - z9) fbavorko oa m`
Oeonpmbs ∑
Sorgcgf`r quo m` sorgo
∐ a 9
4 a (z ∔ 0) a fbavorko sg | z - 0 | = 4 y m` sorgo
∑
a ( z ∔ 0) a fbavorko ∐ a 9 >
>
| z - 0 | = 0 , pbr mb t`atb m` sun` y om prbhuftb ho omm`s fbavorkoa oa | z - 0 | = 0 puos nîa{0,4} > 0 , oatbafos5 sg
∑
4 ∐ a 9
a
a
(z ∔ 0) +
a ( z ∔ 0) ∐ a 9 >
>
∑
∑
a
a
4 (z ∔ 0) .
∑
a
∑
>
(4 a + a )( z ∔ 0) a ∐ a 9
|z-0|=0
sg
>
a ( z ∔ 0) a > 0 . 9 + (0 .0 + 4 . 9) ( z- 0) + (0. 4 + 4. 0 + 8 . 9) ( z- 0)4 +
a 9 a 9 ∐ ∐ + (0 . 6 + 4 . 4 + 8 . 0 + < . 9) ( z- 0) 6 + .... > (z - 0) + 8 (z - 0) 4 + 00 ( z- 0)6 + ..... >
>
, sg | z - 0 | = 0
Α Vorgo ho X`ymbr
c ( a ) ( z 9 ) ( z ∔ z 9 ) a y ost` gku`mh`h v`mo p`r` tbhbs Vg c(z) os `a`mîtgf` oa z9 oatbafos c ( z ) > a! a>9 mbs z portoaofgoatos `m n`ybr fîrfumb `dgortb foatr`hb oa z9 hbaho c(z) os `a`mîtgf`. Bdsorv`r oatbafos quo m` sorgo fbavorko ` c(z) p`r` | z ‖ z9 | = T , sgoahb T om r`hgb hom n`ybr fîrfumb `dgortb foatr`hb oa z9 hbaho c(z) os `a`mîtgf`. ∑
∐
T9
Honbstr`fgöa Vo` z ua fbnpmoeb fu`mqugor` quo vorgcgf` | z ‖ z9 | > T9 = T Vo` F5 | w ‖ z 9 | > π fba
z9 z
F5 |w - z9| > π |w - z9| > T
T9 = π = T
Fbnb z os gatorgbr ` F y so funpmoa tbh`s m`s lgpötosgs ho m` cörnum` ho m` gatokr`m ho F`ufly pbhonbs osfrgdgr5
0 (0 ) 4ωg
c ( z ) >
∪
F
c(w) 0 hw > ( 4 ) 4 ωg w-z ∑
>
0 4 ωg
∪
F
F
c(w) 0 hw > (w - z 9 ) - (z - z 9 ) (6 ) 4ωg
a
∐
∪
F
c(w) z - z 9 (w - z 9 ) 0 w z 9
∑
hw > (8 )
(a)
∑
∐
c(w) z - z hw (>? ) (z ∔ z 9 ) 0 w z 4ωg (w - z 9 ) a> 9 9 a >9 9
∪
a
∪
F
c ( w ) hw > (w - z 9 )a+0 (3 )
∐
( z ∔ z 9 ) c ( z 9 ) a! a>9 a
07
Nöhumb G - _agh`h 8
N`tonàtgf` H
pbr `pmgf`fgöa ho m` cörnum` ho F`ufly, (4) rost`nbs y sun`nbs z9 oa om hoabnga`hbr (0)
(6) (8)
s`f`nbs (w ‖ z9) c`ftbr fbnõa hom hoabnga`hbr
z - z9 T9 z - z9 0 > = 0 , pbr mb t`atb om c`ftbr oatbafos |r| > rosumt` sor m` sun` π w - z9 w - z9 0- r ho ua` sorgo kobnçtrgf` ho r`zöa r fba |r | = 0 , y roonpm`z`nbs hgflb c`ftbr pbr m` sorgo
sg
r>
fbrrospbahgoato. (?) Oa osto p`sb gatorf`ndg`nbs m` gatokr`m fba m` sorgo, p`r` ommb os aofos`rgb nbstr`r quo m` sorgo os uagcbrnonoato fbavorkoato y m` cuafgöa quo m` `fbnp`ð` hodo ost`r `fbt`h` sbdro m` furv` F ( rofbrh`r5 Vg k(z) os ua` cuafgöa `fbt`h` oa H , os hofgr |k(z)| ≨ J p`r` mbs z ho H ⇔ ∑
k(z)c a (z) ∐ a 0
fbavorko uagcbrnonoato oa H y su sun` os k(z). V(z))
>
Oa osto f`sb k(z) >
c ( w ) , hbaho s`donbs quo c(w) , pbr sor `a`mîtgf` sbdro m` furv` F, hodo w ∔ z9
quo |c(w)| pbsoo ua nàxgnb `dsbmutb sbdro F, os hofgr oxgsto ua aõnorb ost`r `fbt`h` (rofbrh`r pbsgtgvb N t`m quo |c(w)|≨5 N), pbr mb t`atb |k(z)| ≨ N / π. a
z - z 9 fbavorko uagcbrnonoato sbdro m` furv` F puos sg w z 9 a > 9 ∑
@honàs m` sorgo
∐
fbnp`r`nbs sus tçrngabs fba mbs ho m` sorgo aunçrgf`
z - z9 w - z9
a
noabr
a
T > 9 , fbnb m` sorgo π quo
0,
pbr
om
a
T 9 vonbs quo ∐ π a > 9 ∑
a
T 9 os fbavorkoato pbr sor kobnçtrgf` fba r`zöa ∐ π a > 9 ∑
frgtorgb
ho
[ogorstr`ss
pbhonbs
`cgrn`r
quo
m`
a
z - z 9 fbavorko uagcbrnonoato sbdro F. Ybr õmtgnb bdsorv`r quo om c`ftbr z ‖ z9 sorgo w z 9 a > 9 ∑
∐
os fbast`ato rospoftb ho m` v`rg`dmo ho gatokr`fgöa w y pbr ommb so l` gahgf`hb `cuor` ho m` gatokr`m (3) so f`mfum` m` gatokr`m `pmgf`ahb om tobron` ho m` horgv`h` ho m` cörnum` ho F`ufly y so bdtgoaoa mbs fbocgfgoatos gahgf`hbs.
Oeonpmb z
0- L`mm`r m` sorgo ho X`ymbr ho c(z) > o `mrohohbr ho z9 > 9
(a)
Y`r` ommb f`mfum`nbs m`s horgv`h`s ho m` cuafgöa, oa osto f`sb s`donbs quo c (a) 9 ov`mu`nbs oa z9 , oa osto oeonpmb c (9) > o > 0 , pbr mb t`atb5 (j )
∑
z
(z) > oz y m`s
∑
j
o > ∐ c j!( 9) ( z ∔ 9) > ∐ j0! z j j >9 j >9 49
Nöhumb G - _agh`h 8
N`tonàtgf` H
om tobron` `sokur` quo m` gku`mh`h so vorgcgf` oa om n`ybr fîrfumb foatr`hb oa z9 hbaho m` cuafgöa os `a`mîtgf`, y fbnb m` oxpbaoafg`m os `a`mîtgf` oa tbhb om pm`ab, m` gku`mh`h `atorgbr v`mo oa
|z| = ∑ b t`ndgça puoho hofgrso quo v`mo ∉z 4- L`mm`r ua` sorgo ho pbtoafg`s ho z quo roprosoato ` m` cuafgöa c(z) >
0 0+ z4
Oa om oauafg`hb abs pghoa ua` sorgo ho pbtoafg`s ho z quo fbavore` ` m` cuafgöa h`h` y pbhonbs bdsorv`r quo c tgoao m` cbrn`
`9 > vorgcgf` 0∔r
∑
` 9 r a , sg ∐ a 9
`9 , quo y` s`donbs os m` sun` ho ua` sorgo kobnçtrgf` y quo 0∔r
| r | = 0 .
>
`9 > 0 y r > -z4 oatbafos pbhonbs osfrgdgr ràpgh`noato
Vg tbn`nbs
∑ ∑ 0 4 4 a a 4a 0 + z4 >∐ a > 9 (-z ) > a > 9 (-0) z sg | - z | = 0 , quo os oqugv`moato ` pohgr quo | z | = 0 ∐
Yuhgnbs oafbatr`r ua` sorgo ho pbtoafg`s ho z quo roprosoat` ` m` c h`h` oa | z | = 0 sga l`dor f`mfum`hb agakua` horgv`h`, quo os mb quo oxgko X`ymbr. M` prokuat` a`tur`m os oatbafos5 m` sorgo l`mm`h`, ² os m` sorgo ho X`ymbr `mrohohbr ho z9 > 9 ho m` c h`h`2 Muokb ho m` prbpgoh`h sgkugoato toahronbs m` rospuost` ` osto gatorrbk`ato.
Α Xobron` ho uagfgh`h ho X`ymbr ∑
Vg
c ( z ) > ∐ a >9
c ( j ) ( z 9 ) f a (z - z 9 ) p`r` | z - z9| = T ⇔ f j > p`r` j > 9, 0, 4,........... j! a
Honbstr`fgöa V`donbs quo
c(z) > f9 + f0 (z - z9) + f4 (z - z9)4 +..........+ fj (z - z9)j +..............., sg | z - z9| = T
Ov`mu`ahb m` cuafgöa oa z9 , bdtoaonbs
c(z9) > f9 , quo vorgcgf` om oauafg`hb p`r` j > 9
Ybr tr`t`rso ho ua` sorgo ho pbtoafg`s, pbhonbs horgv`rm` tçrngab ` tçrngab, bdtoagoahb5
c '(z) > f0 + 4 f4 (z - z9) +..........+ j fj (z - z9)j 0 +..............., sg | z - z9| = T Ov`mu`ahb ost` horgv`h` oa z9 , bdtoaonbs
c '(z9) > f0 , quo vorgcgf` om oauafg`hb p`r` j > 0
Fbnb m` sorgo `atorgbr os ua` sorgo ho pbtoafg`s pbhonbs horgv`rm` auov`noato, bdtoagoahb5
c ''(z) > 4 f4 +..........+ j (j-0) fj (z - z9)j-4 +..............., sg | z - z9| = T 40
Nöhumb G - _agh`h 8
N`tonàtgf` H
Ov`mu`ahb ost` horgv`h` sokuah` oa z 9 , bdtoaonbs vorgcgf` om oauafg`hb p`r`
c ''(z9) > 4f4 , ho hbaho f4 > c ''(z9)/ 4 quo
j>4
Fbatgau`ahb ho m` ngsn` n`aor` puoho bdtoaorso mb dusf`hb.
⊟ Bdsorv`fgbaos 0- _tgmgz`ahb om tobron` `atorgbr vonbs quo sg so tgoao ua` sorgo ho pbtoafg`s ho (z
- z9) quo
∑
fbavorko ` ua` cuafgöa
c(z), os hofgr c (z ) > ∐ f a (z - z 9 ) a oatbafos mbs fbocgfgoatos vorgcgf`a a>9
∑ c ( j ) (z 9 ) c ( z 9 ) , pbr mb t`atb m` sorgo puoho osfrgdgrso c ( z ) > ∐ (z ∔ z 9 )a ho hbaho fa > j! a! a >9
(a )
pbhonbs `cgrn`r quo5
" Xbh` sorgo ho pbtoafg`s ho (z - z9) quo fbavorko ` ua` cuafgöa c(z) os m` sorgo ho X`ymbr ho hgfl` cuafgöa" 4- Os gatoros`ato bdsorv`r quo sg so tgoaoa hbs sorgos ho pbtoafg`s fbavorkoatos fuy` sun` os m` ∑
ngsn` , os hofgr
∐ a 9 >
∑
` a (z ∔ z 9 )a > ∐ d a (z ∔ z 9 )a p`r` | z - z9| = T , oatbafos `a > da , ∉a a >9
Bdsorv`r quo sg c(z) os m` sun` ho f`h` ua` ho omm`s oatbafos , `pmgf`ahb om tobron` ho uagh`h `
c ( a ) ( z 9 ) c ( a ) (z 9 ) f`h` ua` ho omm`s, so bdtgoao ` a > p`r` m` prgnor` sorgo, y d a > p`r` m` sokuah` a! a! sorgo, pbr mb t`atb `a > da , ∉a ∑ 0 > ∐ (-0) a z 4a , sg | z | = 0 y 6- Oa ua oeonpmb `atorgbr lonbs honbstr`hb quo c(z) > 4 0 + z a>9 abs prokuat`nbs sg os` os m` sorgo ho X`ymbr ho m` cuafgöa oa z9 > 9 , `lbr` pbhonbs rospbahor quo sî, `honàs pbhonbs f`mfum`r tbh`s m`s horgv`h`s ho c(z) oa z > 9 .
c ( 64 ) (9) , oatbafos Ybr oeonpmb sg quoronbs l`mm`r c (9) , fbnb s`donbs quo ` 64 > 64! c (64)(9) > 64! `64 , toagoahb prosoato quo `64 os om fbocgfgoato ho m` pbtoafg` 64 , ngr`ahb m` sorgo (64)
fuybs tçrngabs sba
0 + (-0) z4 + (-0)4 z8 -........+ (-0)03 z64 +.........
vonbs quo
`64 > (-0)03 > 0, pbr mb t`atb c ( 64) (9) > 64!
Btrb oeonpmb 5 fbnb
c (69)(9) > 69! `69 y `69 > (-0)0? > -0 , pbr mb t`atb c (69)(9) > - 69!
Os gatoros`ato vor quo tbh`s m`s horgv`h`s ho îahgfo gnp`r, ov`mu`h`s oa 9 , sba tbh`s aum`s puos z ab `p`rofo omov`h` ` ua` pbtoafg` gnp`r y pbr mb t`atb tbhbs mbs fbocgfgoatos ho sudîahgfo gnp`r v`moa 9. 44
Nöhumb G - _agh`h 8
N`tonàtgf` H
Fba rocoroafg` `m ngsnb oeonpmb fbrrospbaho l`for om sgkugoato fbnoat`rgb5 Vg so dusf` m` sorgo ho X`ymbr ho m` cuafgöa ho v`rg`dmo ro`m
c(x) >
0 `mrohohbr ho x > 9 so 0 + x4
bdtgoao ua` sorgo ghçatgf` fba m` v`rg`dmo x oa muk`r ho m` z, porb m` rokgöa ho fbavorkoafg` ho hgfl` sorgo os om gatorv`mb `dgortb (-0,0). Hosho om puatb ho vgst` ho m` tobrî` ho m` v`rg`dmo ro`m, ab l`y a`h` oa om fbnpbrt`ngoatb ho c(x) quo oxpmgquo osto loflb. Yorb fu`ahb ox`nga`nbs m`
0 os `a`mîtgf` oa tbhb 0+ z4 F , oxfoptb oa g y -g. Ybr fbasgkugoato om hos`rrbmmb oa sorgo ho pbtoafg`s `mrohohbr hom 9, os om fîrfumb `dgortb | z | = 0 , fuy` gatorsoffgöa fba om oeo ro`m x h` eust`noato om gatorv`mb g atorv`mb (-0,0)
sgtu`fgöa oa om pm`ab fbnpmoeb, vonbs `m gast`ato quo m` cuafgöa
c ( z ) >
∃ @ftgvgh`h 35 Vg m` sun` ho ua` sorgo ho pbtoafg`s os gku`m ` forb, os hofgr sg
∑
∐ a 9
h a (z ∔ z 9 )a > 9 , ²os fbrroftb
>
`cgrn`r quo ha > 9 , ∉a 2
•Oeorfgfgbs 00- Hos`rrbmm`r m`s cuafgbaos sgkugoatos oa sorgo ho X`ymbr `mrohohbr ho nàxgnb hgsfb hbaho os vàmgh` hgfl` roprosoat`fgöa. `) c 0(z) > soa z
d) c 4(z) > fl z
f) c 6(z) >
0 0∔ z
z9 > 9 o gahgf`r om
04- L`mm`r ua` sorgo ho pbtoafg`s ho z quo roprosoato ` m`s sgkugoatos cuafgbaos us`ahb om oeorfgfgb `atorgbr y eustgcgf`r om prbfohgngoatb5 `) c 6(z) > fbs z
d) c 4(z) > sl z
f) c 6(z) >
0 (0 ∔ z )4
h) c 6(z) > Ma(0-z)
06- L`mm`r ua` sorgo ho pbtoafg`s ho z ‖ z9 quo roprosoato ` m`s sgkugoatos cuafgbaos o gahgf`r m` rokgöa ho v`mghoz. _s`r m` prbpgoh`h ho uagfgh`h.
`) c(z)
> fbs z , z9 > ω /4
h) j(z) >
z z4 ∔ 0
d) k(z) > z. o
, z9 > g
o) m(z) > 6z
6
4z
, z9 > 0
f)
l( z ) >
4 z∔6
, z9 > -4
z4 ∔ 0 c) n( z ) > , z9 > 6 z
‖ 4z , z9 > - g
46
Nöhumb G - _agh`h 8
N`tonàtgf` H
(z ∔ g )4a , c(z) > ∐ + a 0 a >0
∑
∑
08- H`h`s
k(z) > ∐ (0 + g ) a (z ∔ 4 )4a +0 a >0
`) L`mm`r om hbngagb ho `a`mgtgfgh`h ho c(z) y k(z) `) F`mfum`r c '(g) , c (3)(g) , c (7)(g) , k‗(4) , c (3)(4) , c (0;)(4)
♣ Forbs ho ua` cuafgöa `a`mîtgf` ♣ Hofgnbs quo z9
os ua forb ho c(z) sg c(z9) > 9
♣ Hofgnbs quo z9 y c (j )(z9) ≩ 9
os ua forb ho brhoa j ho c(z) sg c(z9) > c'(z9) > c''(z9) >......> c (j - 0)(z9) > 9
Oeonpmbs 6
Y`r` l`mm`r mbs forbs ho c(z) > z soa z , pm`ato`nbs c(z) > 9 y rosbmvonbs ost` ofu`fgöa , oa osto f`sb so vorgcgf` quo c(jω) > 9 fba j > 9, ° 0 , ° 4, ..... , pbr mb t`atb ost` cuafgöa tgoao gacgagtbs forbs. 4 6 Y`r` l`mm`r om brhoa ho f`h` forb l`y quo f`mfum`r m` horgv`h` c '(z) > 6 z soa z + z fbs z y ov`mu`rm` oa tbhbs forbs l`mm`hbs , oa osto f`sb5
c' (9) > 9 y c' (jω) ≩ 9, p`r` j oatorb y hgstgatb ho 9 fbnb m` prgnor` horgv`h` ab so `aum` oa ω, -ω , 4ω, -4ω, forbs ho brhoa 0, t`ndgça mm`n`hbs forbs sgnpmos ho c(z).
......., hofgnbs quo tbhbs ommbs sba
M` sgtu`fgöa os hgstgat` sg z > 9 puos c' (9) > 9 , fu`ahb ostb bfurro l`y quo f`mfum`r c ''(z) y ov`mu`r c ''(9), quo oa osto oeonpmb vuomvo ` h`r 9, oatbafos l`y quo f`mfum`r c '''(z) y ov`mu`r c'''(9) y `sî so sgkuo l`st` oafbatr`r om brhoa ho m` prgnor` horgv`h` quo ab so `aum` oa om forb quo ost`nbs `a`mgz`ahb. Osto prbfosb puoho sor m`rkb y `durrghb, pbr ommb os fbavoagoato hos`rrbmm`r m` cuafgöa oa sorgo ho X`ymbr `mrohohbr hom forb quo protoahonbs fm`sgcgf`r, oa osto f`sb hgfl` sorgo os.
z6 z3 8 z soa z > z z ( z ∔ + .......) > z ∔ + ...... , fbavorkoato p`r` tbhb z 6! 6! 6
6 6
Bdsorv`ahb m` sorgo bdtoagh` y us`ahb om tobron` ho uagfgh`h ho m` sorgo ho X`ymbr, X`ymbr, pbhonbs `cgrn`r quo c (9) > 9, c ' (9) > 9 , c ''(9) > 9 , c ''' (9) > 9 , c ''''(9) ≩ 9 , pbr mb t`atb z > 9 os ua forb ho brhoa 8 ho c(z)
48
Nöhumb G - _agh`h 8
N`tonàtgf` H
Α F`r`ftorgz`fgöa ho forbs `) Vg z9 os ua forb ho brhoa j ho m` cuafgöa `a`mîtgf` c(z) ⇔ c(z) > (z - z9)j k(z) , fba k(z) `a`mîtgf` oa z9 y k(z9) ≩ 9 j d) Vg c(z) > (z - z9) k(z) , fba k(z) `a`mîtgf` oa z9 y k(z9) ≩ 9 ⇔ z 9 os ua forb ho brhoa j ho m` cuafgöa c(z)
Honbstr`fgöa `) Ybr sor z9 ua forb ho brhoa j ho c(z) s`donbs quo c(z9) > c '(z9) > c ''(z9) >....> c (j-0)(z9) > 9 (j) y c (z9) ≩ 9 oatbafos su hos`rrbmmb ho X`ymbr `mrohohbr hom puatb z9 sorà fbavorkoato oa ua fîrfumb |z - z9| = T y tgoao m` cbrn` 5 (j )
c (z) >
c (z 9 )
(z ∔ z 9 ) j +
(j +0)
c
( j ) ( j 0 ) + c (z 9 ) c (z 9 ) (z 9 ) + (z ∔ z 9 )0 + ...... (z ∔ z 9 )j+0 + ...... > (z ∔ z 9 )j 088 8 8 8 6 +4 (j8 0)!88 8 8 8 8 j! k( z )
(j + 0)!
j!
j
pbr mb t`atb c(z) > (z - z9) k(z) , hbaho k(z) os `a`mîtgf` oa z9 pbr sor ua` sorgo ho pbtoafg`s fbavorkoato oa |z - z9| = T y `honàs k(z9) ≩ 9 puos ov`mu`ahb m` sorgo quo hocgao ` k oa z9 so bdsorv` quo so `aum`a tbhbs mbs tçrngabs s`mvb om prgnorb, quo os c (j)(z9) / j! ≩ 9, pbr mb t`atb k(z9) ≩ 9 j
d) V`donbs quo c(z) > (z - z9) k(z) , hbaho k(z) os `a`mîtgf` oa z9 y `hngto ua hos`rrbmmb oa sorgo ho X`ymbr ho m` cbrn`
k(z9) ≩ 9, pbr mb t`atb k(z)
k (a ) ( z 9 ) k(z) > ∐ ( z ∔ z 9 ) a , oa |z - z9| = T*, numtgpmgf`ahb `ndbs ngondrbs pbr (z - z9)j a! a>9 ∑ ∑ k (a) (z 9 ) j a+j a +j a 9 9 sg |z - z9| = T*, bdtoaonbs (z - z9) k(z) > a > 9 a >9 f ( z ∔ z ) ∐ ∐ a! (z ∔ z ) > ∐ ∑
(a)
(bdsorv`r quo oa om õmtgnb p`sb lonbs hoabnga`hb fa `m fbfgoato k ∑
(z9) / a! )
f a (z ∔ z 9 ) a j > f9 (z - z9)j + f0 ( z - z9)j+0 +.........., fba ∐ ∐ a 9
pbr mb t`atb c(z) >
+
f9 > k(z9) ≩ 9
>
fbnb c(z) puhb oxpros`rso fbnb ua` sorgo ho pbtoafg`s pbsgtgv`s ho (z - z9) , pbr om tobron` ho uagfgh`h s`donbs quo çst` os m` sorgo ho X`ymbr ho c(z) , pbr mb t`atb pbhonbs `cgrn`r quo 5 (j-0)
(j)
c(z9) > c (z9) > c (z9) >....> c (z9) > 9 z9 os ua forb ho brhoa j ho c(z)
f9 > c (z9) /j! ≩ 9 , ho hbaho so hosproaho quo
y
∃ @ftgvgh`h ;5 Vg z9 os ua forb ho brhoa p ho tobron` `atorgbr quo5
c(z) y os ua forb ho brhoa q ho k(z), eustgcgf`r fba m` `yuh` hom 4?
Nöhumb G - _agh`h 8
N`tonàtgf` H
`) z9 os ua forb ho brhoa
p + q hom prbhuftb c(z). k(z)
d) sg p = q , z9 os ua forb ho brhoa p ho c(z) ° k(z) f) sg p > q , z9 os ua forb ho brhoa n`ybr b gku`m quo p ho
c(z) ° k(z)
•Oeorfgfgbs 0?- Eustgcgf`r oa f`h` f`sb quo z9 os ua forb ho m` cuafgöa o gahgf`r su brhoa `) k0(z) > z6 (0 ‖
fbs z) , z9 > 9
f) k6(z) > 8z ‖ tk ( ωz)
d) k4(z)
> soa4 z (0 + fbs z) , z9 > ω
h) k8(z) > 3 soa (z4) + z3 - 3z4 ,
, z9 > ½
z9 > 9
c(z) y k(z) sba `a`mîtgf`s oa z9 , c(z9) > k(z9) > 9 y k‗(z9) ≩ 9 , honbstr`r m` rokm` ho M‗Lbspgt`m 5 mîn c ( z ) > c ' ( z 9 ) z ↔ z 9 k( z ) k' (z 9 )
03- Vg
Α Vorgo ho M`uroat Vg c(z) os `a`mîtgf` oa om `agmmb r = tbhbs mbs z ho hgflb `agmmb v`mo quo5
| z - z9| = T (r puoho sor 9 y T puoho sor ∑ ) oatbafos p`r`
F
∑
a
∑
∔a
a > 9 ` a ( z ∔ z 9 ) + a >0 d a ( z ∔ z 9 ) c (z ) > ∐ ∐
hbaho
`a >
0 c(w) 0 c(w) y > d hw hw a 4ωg ∪F ( w ∔ z 9 ) -a +0 4ωg ∪F (w ∔ z 9 ) a +0
sgoahb F ua` furv` forr`h` fbatoagh` oa om `agmmb quo oafgorr` ` z9
Honbstr`fgöa
z9
F
z9
Vo` z ua fbnpmoeb fu`mqugor` quo vorgcgf` | z ‖ z9 | > T9 fba r = T9 = T
F4
T9 = π0 = T
Vo` F05 | w ‖ z9 | > π0 fba
F0
F45 | w ‖ z9 | > π4 fba r = π4 = T9
z 43
Nöhumb G - _agh`h 8
N`tonàtgf` H
Fbnb z os gatorgbr `m `agmmb hotornga`hb pbr m`s fgrfuacoroafg`s F 0 y
F4 y c(w) os `a`mîtgf` sbdro
hgfl`s furv`s y oa m` rokgöa mgngt`h` pbr omm`s, pbhonbs utgmgz`r om rosumt`hb bdtoaghb oa m` `ftgvgh`h 09 ho m` uagh`h 6 , quo abs `sokur` quo5 5
c ( z ) >
0 c ( w ) 0 c ( w ) hw hw (lonbs f`ndg`hb z9 pbr z y z pbr w) ∪ ∪ 4ωg F0 w ∔ z 4ωg F4 w ∔ z
` p`rtgr ho `quî tr`d`e`nbs fbnb oa m` honbstr`fgöa ho m` sorgo ho X`ymbr, os hofgr sun`nbs y rost`nbs z9 oa mbs hoabnga`hbros, bdtoagoahb5
c ( z ) >
0 c(w) 0 c(w) hw hw ∪ ∪ 4ωg F0 (w - z 9 ) - (z - z 9 ) 4ωg F4 (w - z 9 ) - (z - z 9 )
`lbr` s`f`nbs c`ftbr fbnõa (w - z9) hom hoabnga`hbr ho m` prgnor` y s`f`nbs c`ftbr fbnõa (z -z9) hom hoabnga`hbr ho m` sokuah`, bdtoagoahb5
c ( z ) >
0 4ωg ∪F0
c(w)
(w - z 9 )0
z - z9 w - z 9
hw +
0 4ωg ∪F4
c(w) hw w - z9 (z - z 9 )0 z - z9
Ngr`ahb ost`s gatokr`mos hosfudrgnbs quo uab hgvghghb mbs fbrflotos so fbrrospbahoa fba m` sun` ho ua` sorgo kobnçtrgf`, oa m` prgnor` gatokr`m om nöhumb ho su r`zöa os
z ∔ z9 T9 > = 0 y oa m` sokuah` om nöhumb ho su r`zöa os w ∔ z 9 π0
w ∔ z9 π4 = 0 , pbr mb t`atb > z ∔ z9 Tb
`nd`s oxprosgbaos so puohoa roonpm`z`r pbr sorgos kobnçtrgf`s fbavorkoatos , bdtoagoahb5 a
a
z - z 9 w - z 9 0 c(w) ∑ hw c ( z ) > hw + 0 4 F F a >9 a >9 w - z 9 z - z 9 4ωg ∪ (w - z 9 ) ∐ 4ωg ∪ (z - z 9 ) ∐
0
c(w)
∑
fbnb oa m` honbstr`fgöa hom tobron` ho X`ymbr, auov`noato puoho honbstr`rso quo hgfl`s sorgos sba uagcbrnonoato fbavorkoatos y quo m`s cuafgbaos quo numtgpmgf`a hgfl`s sorgos ostàa `fbt`h`s sbdro m`s furv`s ho gatokr`fgöa, pbr mb t`atb puoho us`rso quo m` gatokr`m ho ua` sorgo os gku`m ` m` sorgo ho m`s gatokr`mos, bdtoagoahb5
c ( z ) >
∑
(z ∔ z )
a
0
c(w)
hw +
∑
( z ∔ z ) ∔ ( a + 0)
0
c(w) (w - z ) a hw
∐ a 9
4ωg ∪F0 (w - z 9 ) a +0
9
>
(mbs c`ftbros (z- z9)
∐ a 9
9
>
4ωg ∪F4
9
a
y (z - z9)-(a+0) ab hopoahoa ho w , pbr ommb mbs s`f`nbs `cuor` ho m` gatokr`m)
sg mm`n`nbs
y d a +0 > 0 F c(w) (w - z 9 ) a hw > 0 F ` a > 40ωg ∪F0 ( w ∔c(w) 4ωg ∪ 4 4ωg ∪ 4 ( w c(w) ∔ z 9 ) -a hw z 9 ) a +0 hw
4;
Nöhumb G - _agh`h 8
N`tonàtgf` H
hbaho oa ost` õmtgn` os gnpbrt`ato bdsorv`r quo
0 c(w) 0 c(w) d a > 4ωg ∪F4 ( w ∔ z 9 ) -(a-0) hw > 4ωg ∪F4 ( w ∔ z 9 ) -a +0 hw ∑
oatbafos
∑
c ( z ) > ∐ ( z ∔ z 9 ) ` a + ∐ ( z ∔ z 9 ) ∔(a +0) d a+0 , a
a >9
a>9
sg oa ost` sokuah` sorgo f`ndg`nbs a pbr a -0 , bdtoaonbs5 ∑
c ( z ) > ∐ ( z ∔ z 9 ) ` a + a >9
a
∑
( z ∔ z 9 ) a d a , quo os oqugv`moato ` mb quo quorî`nbs honbstr`r. ∐ a -0 9 ∔
>
Vömb quoh` pbr vor quo mbs fbocgfgoatos `a y da puohoa bdtoaorso gatokr`ahb sbdro ua` furv` F , fbatoagh` oa om `agmmb ho `a`mgtgfgh`h y ab sbdro m`s furv`s F0 y F4, porb ostb mb hoe`nbs fbnb ua` `ftgvgh`h p`r` om `munab.
⊟ Bdsorv`fgöa sbdro m`s sorgos ho X`ymbr y M`uroat 0- Vg
c(z) os `a`mîtgf` oa z9 , os hofgr os `a`mîtgf` oa ua fîrfumb `dgortb foatr`hb oa z9 ho r`hgb T ⇔ c(z) puoho hos`rrbmm`rso oa sorgo ho pbtoafg`s pbsgtgv`s ho (z - z9 ) (sorgo ho X`ymbr) y hgfl` sorgo fbavorko y roprosoat` ` c(z) oa | z - z9| = T
c(z) os `a`mîtgf` oa ua `agmmb `dgortb foatr`hb oa z9 , os hofgr sg c(z) os `a`mîtgf` oa r = | z - z9| = T ⇔ c(z) puoho hos`rrbmm`rso oa sorgo ho pbtoafg`s pbsgtgv`s y/9 aok`tgv`s ho (z - z9 ) (sorgo ho M`uroat) y hgfl` sorgo fbavorko y roprosoat` ` c(z) oa r = | z - z9| = T
4- Vg
Oeonpmbs
Mbs fbocgfgoatos ho m` sorgo ho M`uroat ab so suomoa dusf`r f`mfum`ahb m`s gatokr`mos quo hocgaoa ` `a y da , sgab pbr btrbs nçtbhbs quo so oxpmgf`a oa mbs sgkugoatos oeonpmbs y ostb so hodo ` quo, fbnb bfurro fba m` sorgo ho X`ymbr, tbh` sorgo fbavorkoato ho pbtoafg`s pbsgtgv`s y aok`tgv`s os m` sorgo ho M`uroat ho m` cuafgöa sun` y pbr mb t`atb os õagf`.
"p`r` hos`rrbmm`r ua` cuafgöa oa sorgo ho M`uroat so oxgko quo m` cuafgöa so` `a`mîtgf` oa ua `agmmb, sg om `agmmb ostà foatr`hb oa z9 oatbafos m` Os nuy gnpbrt`ato toaor oa fuoat` quo5
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