Q. If $\omega( \neq 1)$ be a cube root of unity and $\left( 1 + \omega^{2} \right)^{n} = \left( 1 + \omega^{4} \right)^{n}$, then the least positive value of $n$ is

A) 2
B) 3
C) 5
D) 6
Explanation

(b)
We have, $\left( 1 + \omega^{2} \right)^{n} = \left( 1 + \omega^{4} \right)^{n}$
$\Rightarrow \ \ \ \ ( - \omega)^{n} = \left( - \omega^{2} \right)^{n}$
$\Rightarrow \ \ \ \omega^{n} = 1$
$\Rightarrow \ \ \ \ \ \ n = 3$ is least positive value of $n$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.