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Evaluate the Following Determinant: ∣ ∣ ∣ ∣ 1 − 3 2 4 − 1 2 3 5 2 ∣ ∣ ∣ ∣ - Mathematics

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Question

Evaluate the following determinant:

\[\begin{vmatrix}1 & - 3 & 2 \\ 4 & - 1 & 2 \\ 3 & 5 & 2\end{vmatrix}\]

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Solution

\[∆ = \begin{vmatrix}1 & - 3 & 2 \\ 4 & - 1 & 2 \\ 3 & 5 & 2\end{vmatrix}\]
\[ = 1\begin{vmatrix}- 1 & 2 \\ 5 & 2\end{vmatrix} - ( - 3)\begin{vmatrix}4 & 2 \\ 3 & 2\end{vmatrix} + 2\begin{vmatrix}4 & - 1 \\ 3 & 5\end{vmatrix}\]
\[ = 1\left( - 2 - 10 \right) + 3\left( 8 - 6 \right) + 2\left( 20 + 3 \right)\]
\[ = ( - 12) + 6 + 46\]
\[ = 40\]

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Chapter 6: Determinants - Exercise 6.2 [Page 57]

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RD Sharma Mathematics [English] Class 12
Chapter 6 Determinants
Exercise 6.2 | Q 1.4 | Page 57

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