Terry Lee - Advanced Mathematics 7th Edition (2012)

Will always intersect at y=1 because the square root of 1 is 1.

Value of x that makes the derivative undefined is the vertical tangent i.e. Value of x that makes the denominator of the derivative=0.

If the grad is -infinite as x approaches 1 from the negative side and grad is +infinite as x approaches 1 from positive side, there will be a cusp

(X-2) is an example of indeterminable

E.g. (X-2)

Exists where f(x) is above the x-axis

Coordinates of vertical tangents

If using part a, need to draw out complex number z in order to find arg(z).

If f double dash does not give 0, therefore it must be double zero

OA=iOB indicates same length (modulus) with the i indicating a rotation of 90