Originally Posted by

**Ian1779** eg. The seventh roots of -128 are:

$\displaystyle z_{0} = \langle2,\pi/7\rangle$

$\displaystyle z_{1} = \langle2,3\pi/7\rangle$

$\displaystyle z_{2} = \langle2,5\pi/7\rangle$

$\displaystyle z_{3} = \langle2,\pi\rangle = -2$

$\displaystyle z_{4} = \langle2,9\pi/7\rangle$

$\displaystyle z_{5} = \langle2,11\pi/7\rangle$

$\displaystyle z_{6} = \langle2,13\pi/7\rangle$

Do I need to be displaying them like this?

$\displaystyle z_{0} = \langle2,\pi/7\rangle = 2(cos(\pi/7)+isin(\pi/7))$

I think that really up to your instructor/textbook

The reason I ask is because i'm asked to show how they make 3 complex conjugate pairs which I can see are

$\displaystyle z_{0}$ and $\displaystyle z_{6}$

$\displaystyle z_{1}$ and $\displaystyle z_{5}$

$\displaystyle z_{2}$ and $\displaystyle z_{4}$