Question

If matrix $A=\left[\begin{array}{cc}2x& -4\\ -2& x\end{array}\right]$ is singular, then the value(s) of $x$ can be

• A. $0$
• B. $-1$
• C. $-2$
• D. $2$

Answer 1

Answer: (C), (D)

$2$

Given : $A=\left[\begin{array}{cc}2x& -4\\ -2& x\end{array}\right]$
For singular matrix, $\text{det}\left(A\right)=0$
$\Rightarrow 2x^2-8=0\Rightarrow x=\pm 2$