### Home > PC3 > Chapter 13 > Lesson 13.1.2 > Problem13-25

13-25.

Let $z=9\left(\cos\left(\frac{5\pi}{4}\right)+i\sin\left(\frac{5\pi}{4}\right)\right)$.

1. What are the fourth roots of $z$?

1. Evaluate $z^{5}$.

$r=9,θ=\frac{5\pi}{4}$