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∣ ∣ ∣ ∣ ∣ 0 B 2 a C 2 a A 2 B 0 C 2 B a 2 C B 2 C 0 ∣ ∣ ∣ ∣ ∣ = 2 a 3 B 3 C 3 - Mathematics

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प्रश्न

\[\begin{vmatrix}0 & b^2 a & c^2 a \\ a^2 b & 0 & c^2 b \\ a^2 c & b^2 c & 0\end{vmatrix} = 2 a^3 b^3 c^3\]

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उत्तर

\[∆ = \begin{vmatrix}0 & b^2 a & c^2 a \\ a^2 b & 0 & c^2 b \\ a^2 c & b^2 c & 0\end{vmatrix}\]

\[ = \frac{1}{abc}\begin{vmatrix}0 & b^3 a & c^3 a \\ a^3 b & 0 & c^3 b \\ a^3 c & b^3 c & 0\end{vmatrix} \left[\text{ Multiplying the three columns by a, b and c }\right]\]

\[\]

\[ = \frac{abc}{abc}\begin{vmatrix}0 & b^3 & c^3 \\ a^3 & 0 & c^3 \\ a^3 & b^3 & 0\end{vmatrix} \left[\text{ Taking out a, b and c common from the three rows }\right] \]

\[ = b^3 \begin{vmatrix}a^3 & c^3 \\ a^3 & 0\end{vmatrix} + c^3 \begin{vmatrix}a^3 & 0 \\ a^3 & b^3\end{vmatrix} = 2 a^3 b^3 c^3 \left[\text{ Expanding along }R_1 \right]\]

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अध्याय 6: Determinants - Exercise 6.2 [पृष्ठ ६०]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 6 Determinants
Exercise 6.2 | Q 34 | पृष्ठ ६०

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