Question

If $A(\ne O)$ is a skew-symmetric matrix of order $2\times 2$ which is formed with $0$ and $i,$ then the determinant of matrix is
(where $i=\sqrt{-1}$)

• A. $0$
• B. $2i$
• C. $-1$
• D. $1$

Answer 1

The correct option is C $-1$

From given condition, only possible matrix is $\left[\begin{array}{cc}0& i\\ -i& 0\end{array}\right]$ or $\left[\begin{array}{cc}0& -i\\ i& 0\end{array}\right]$

$\therefore |A|=i^2=-1$