1)

$If\omega =\frac{-1 + \sqrt{3i}}{2} $ then $ (3+\omega+\omega^{2})^4$ is


A) 16

B) -16

C) $16\omega$

D) $16\omega^{2}$

Answer:

Option C

Explanation:

Let $\omega =\frac{-1 + \sqrt{3i}}{2}$

Now, 1+ ω + ω2 = 0 and  ω3= 1

$then (3+\omega+\omega^{2})^4$ 

= (3+ω+3ω2+2ω-2ω)4 =(3+3ω+3ω2-2ω)4

= [3(1+2+ω2)-2ω]4 = (0-2ω)4 = 16ω4 = 16ω (ω3 = 1 )