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QUESTION

Calculate the determinant of the matrix
$\textbf{A}=\left(\begin{array}{ccc}3&-1&0\\1&2&1\\2&-2&1\end{array}\right).$



ANSWER

$\det{\bf A}
=\left|\begin{array}{ccc}3&-1&0\\1&2&1\\2&-2&1\end{array}\right|
=3(2-(-2))-1(2-1)+0=3(4)-1+0=11$




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