Question

Find the cube roots of 8(cos 216° + i sin 216°).

Answer 1

@jagatuba

Answer 2

@Luigi0210

Answer 3

What math is this?

Answer 4

Pre-Cal

Answer 5

I don't think I've ever done something like this..

Answer 6

r = 8 (cos216 + isin 216)
\(r^{1/3} = 8^{1/3}(cos (\dfrac{216}{3})+isin(\dfrac{216}{3})\) = \(2(cos(72) + isin (72))\)

Answer 7

That's called De Moivre's theorem

Answer 8

okay thanks for explaining it to me!I see you plug it in for me as well thanks for that!