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If a = [ 1 2 3 − 1 ] and B = [ 1 0 − 1 0 ], Find |Ab|. - Mathematics

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प्रश्न

If \[A = \begin{bmatrix}1 & 2 \\ 3 & - 1\end{bmatrix}\text{ and }B = \begin{bmatrix}1 & 0 \\ - 1 & 0\end{bmatrix}\] , find |AB|.

 
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उत्तर

\[A = \begin{bmatrix} 1 & 2\\3 & - 1 \end{bmatrix} \] 
\[B = \begin{bmatrix} 1 & 0 \\ - 1 & 0 \end{bmatrix} \] 
\[AB = \begin{bmatrix} 1 & 2\\3 & - 1 \end{bmatrix}\begin{bmatrix} 1 & 0\\ - 1 & 0 \end{bmatrix} = \begin{bmatrix}1 - 2 & 0 + 0 \\ 3 + 1 & 0 + 0\end{bmatrix} = \begin{bmatrix}- 1 & 0 \\ 4 & 0\end{bmatrix}\] 
\[\left| AB \right| = 0 - 0 = 0\]

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अध्याय 6: Determinants - Exercise 6.6 [पृष्ठ ९०]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 6 Determinants
Exercise 6.6 | Q 9 | पृष्ठ ९०

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