Write z = (–1 + i) in polar form.

we have, z = (–1 + i)

Let -1 = rcosθ and √3 = rsinθ

By squaring and adding, we get

(-1)² + (√3)² = (rcosθ)² + (rsinθ)²

⇒ 1+3 = r²(cos²θ + sin²θ)

⇒4 = r²

⇒ r = 2

Since, θ lies in second quadrant, we have

Thus, the required polar form is