If z = 2cis 60°, find z^4 in rectangular form.

Answer 1

z = 2 cosine 60 + 2 i sin 60

z= 2 e^i(60)

z^4 = 16 e^i(240)
= 16 cos 240 + 16 i sin 240
= 16 (-.5 )+ 16 i(-.866 )
= -8 - 13.86 i

Answer 2

-8-8/3i