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Without Expanding, Show that the Value of the Following Determinant is Zero: ∣ ∣ ∣ ∣ 6 − 3 2 2 − 1 2 − 10 5 2 ∣ ∣ ∣ ∣

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Question

Without expanding, show that the value of the following determinant is zero:

\[\begin{vmatrix}6 & - 3 & 2 \\ 2 & - 1 & 2 \\ - 10 & 5 & 2\end{vmatrix}\]

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Solution

\[ ∆ = \begin{vmatrix}6 & - 3 & 2 \\ 2 & - 1 & 2 \\ - 10 & 5 & 2\end{vmatrix}\]
\[ = \begin{vmatrix}0 & - 3 & 2 \\ 0 & - 1 & 2 \\ 0 & 5 & 2\end{vmatrix} \left[ \text{Applying }C_1 \to C_1 + 2 C_2 \right]\]
\[ \Rightarrow ∆ = 0\]

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Chapter 5: Determinants - Exercise 6.2 [Page 57]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 5 Determinants
Exercise 6.2 | Q 2.02 | Page 57

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