question: suppose that

$\displaystyle E = (\frac{1+\sqrt 3 i}2)^n+(\frac{-1+\sqrt 3 i}2)^n$

where n is a natural no.

find the value of E for

a) n = 3k

b) n = 3k +1

c) n = 3k + 2

where k is an odd no.

sorry that i don't type my malfunction workings.

thanks!