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Question
If A is a square matrix, then AA is a
Options
skew-symmetric matrix
symmetric matrix
diagonal matrix
none of these
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Solution
none of these
Given: A is a square matrix.
\[Let A = \begin{bmatrix}1 & 2 \\ 1 & 0\end{bmatrix}\]
\[ \Rightarrow AA = \begin{bmatrix}1 & 2 \\ 1 & 0\end{bmatrix}\begin{bmatrix}1 & 2 \\ 1 & 0\end{bmatrix} = \begin{bmatrix}3 & 2 \\ 1 & 2\end{bmatrix}\]
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