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If X ∈ N and ∣ ∣ ∣ X + 3 − 2 − 3 X 2 X ∣ ∣ ∣ = 8, Then Find the Value of X. - Mathematics

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प्रश्न

If x ∈ N and \[\begin{vmatrix}x + 3 & - 2 \\ - 3x & 2x\end{vmatrix}\]  = 8, then find the value of x.

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उत्तर

\[\begin{vmatrix}x + 3 & - 2 \\ - 3x & 2x\end{vmatrix}\]  = 8

\[\Rightarrow \left( x + 3 \right)2x - \left( - 2 \right)\left( - 3x \right) = 8\]
\[ \Rightarrow 2 x^2 + 6x - 6x = 8\]
\[ \Rightarrow 2 x^2 = 8\]
\[ \Rightarrow x^2 - 4 = 0\]
\[ \Rightarrow x^2 = 4\]
\[ \Rightarrow x = 2 \left[ x \neq - 2 \because x \in N \right]\]

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अध्याय 6: Determinants - Exercise 6.6 [पृष्ठ ९५]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 6 Determinants
Exercise 6.6 | Q 54 | पृष्ठ ९५

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