# Math Help - complex polar form

1. ## complex polar form

$z^4 = -1$
Why is $z=e^{mi \pi {1 \over 4}}$ in polar form?
m is an odd integer

2. Originally Posted by bigdoggy
$z^4 = -1$
Why is $z=e^{mi \pi {1 \over 4}}$ in polar form?
m is an odd integer
Do you know how to express -1 in polar form? Are you familiar with deMoivre's Theorem?

3. Originally Posted by mr fantastic
Do you know how to express -1 in polar form? Are you familiar with deMoivre's Theorem?
Hi

Thanks...I see it is just an application of De Moivre!