How to express z= 1/(1-i) in polar form?

1 Answer
May 2, 2017

Simplify into a + bi form first

Explanation:

z = 1/(1-i) = 1/(1-i)*(1+i)/(1+i) = (1+i)/2 = 1/2 + i/2

Now find r = | z |.

|z| = sqrt(1/4 + 1/4) = sqrt(2/4) = sqrt(2)/2

In Quadrant 1, theta = arctan(b/a) = arctan(1) = pi/4.

Therefore, z = (sqrt(2)/2)(cos(pi/4) + isin(pi/4)).