Question
If $A=\left[a_{i j}\right]$ is a square matrix of order 2 such that $a_{i j}=\left\{\begin{array}{ll}1, & \text { when } i \neq j \\ 0, & \text { when } i=j\end{array}\right.$ then $A^2$ is

Answer

(b) $\left[\begin{array}{ll}1 & 0 \\ 0 & 1\end{array}\right]$
Explanation:$\left[\begin{array}{ll}1 & 0 \\ 0 & 1\end{array}\right]$

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