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Question
Evaluate the following determinant:
\[\begin{vmatrix}6 & - 3 & 2 \\ 2 & - 1 & 2 \\ - 10 & 5 & 2\end{vmatrix}\]
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Solution
\[ ∆ = \begin{vmatrix}6 & - 3 & 2 \\ 2 & - 1 & 2 \\ - 10 & 5 & 2\end{vmatrix}\]
\[ = 6( - 2 - 10) - ( - 3)(4 + 20) + 2(10 - 10)\]
\[ = - 72 + 72 + 0\]
\[ = - 72 + 72\]
\[ = 0\]
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