Q. The number of real roots of the equation $\left( x + \frac{1}{x} \right)^{3} + x + \frac{1}{x} = 0$ is

A) 0
B) 2
C) 4
D) 6
Explanation

(a)
$\left( x + \frac{1}{x} \right)^{3} + \left( x + \frac{1}{x} \right) = 0$
$\Rightarrow \ \ \left( x + \frac{1}{x} \right)\left\lbrack \left( x + \frac{1}{x} \right)^{2} + 1 \right\rbrack = 0$
$\Rightarrow x + \frac{1}{x} = 0$
$\Rightarrow x^{2} = - 1$ which is not possible
Hence, no real roots exist

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

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