If x^2 + 1x^2 = 2 , then the value of x - 1x is?

Answer: Option B

$$\begin{array}{rl}& x^2+\frac{1}{x^2}=2\\ & \Rightarrow {\left(x-\frac{1}{x}\right)}^2+2.x.\frac{1}{x}=2\\ & \Rightarrow x-\frac{1}{x}=2-2\\ & \Rightarrow x-\frac{1}{x}=0\end{array}$$