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QUESTION

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

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ANSWER

$\det\mathbf{A}=1\left|\begin{array}{ccc}2&0&1\\0&1&2\\3&2&0\end{array}\right|
=2\{1(0)-2(2)\}+0+1\{0(2)-1(3)\}=2(0-4)+1(0-3)=-8-3=-11$




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