Math Help - Use complex numbers to solve problems

1. Use complex numbers to solve problems

Use De Moivre's theorem to simplify the following. Leave your answers in the polar form r cis θ.

a) [2(cos π/4 + i sin π/4)]^5

b) [√2(cos π/6 - i sin π/6)]^4

2. a) 32cis 5pie/4

b) 4cis -2pie/3