If is a complex cube root of unity, then 1 +1 ^2 = - Vidyadip

MCQ

If $\omega$ is a complex cube root of unity, then $\frac{1}{\omega}+\frac{1}{\omega^2}$ =

A
1
✓
$-1$
C
$\frac{1}{\omega}$
D
$-\frac{1}{\omega}$

✓

Answer

Correct option: B.

$-1$

(B)
$\frac{1}{\omega}+\frac{1}{\omega^2}=\frac{\omega+\omega^2}{\omega^3}=\frac{-1}{1}=-1$

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