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Write the value of the determinant |2345686x9x12x| - Mathematics

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Question

Write the value of the determinant \[\begin{vmatrix}2 & 3 & 4 \\ 5 & 6 & 8 \\ 6x & 9x & 12x\end{vmatrix}\]

Sum
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Solution

\[\begin{vmatrix}2 & 3 & 4 \\ 5 & 6 & 8 \\ 6x & 9x & 12x\end{vmatrix}\] 
\[ = \begin{vmatrix}2 & 3 & 4 \\ 5 & 6 & 8 \\ 2 & 3 & 4\end{vmatrix} \left[\text{ Taking 3x common from }R_3 \right]\] 
\[ = 0 \left[ \because R_1\text{ and }R_3\text{ are identical }\right]\] 

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Chapter 6: Determinants - Exercise 6.6 [Page 91]

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RD Sharma Mathematics [English] Class 12
Chapter 6 Determinants
Exercise 6.6 | Q 38 | Page 91

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