मराठी

Without Expanding, Show that the Value of the Following Determinant is Zero: ∣ ∣ ∣ ∣ ∣ 1 / a A 2 B C 1 / B B 2 a C 1 / C C 2 a B ∣ ∣ ∣ ∣ ∣ - Mathematics

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प्रश्न

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

\[\begin{vmatrix}1/a & a^2 & bc \\ 1/b & b^2 & ac \\ 1/c & c^2 & ab\end{vmatrix}\]

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उत्तर

\[ ∆ = \begin{vmatrix}\frac{1}{a} & a^2 & bc \\ \frac{1}{b} & b^2 & ac \\ \frac{1}{c} & c^2 & ab\end{vmatrix}\]
\[ = \begin{vmatrix}1 & a^3 & abc \\ 1 & b^3 & abc \\ 1 & c^3 & abc\end{vmatrix} \left[ \text{ Applying } R_1 \to a R_1 , R_2 \to b R_2 and R_3 \to c R_3 \right]\]
\[ = abc\begin{vmatrix}1 & a^3 & 1 \\ 1 & b^3 & 1 \\ 1 & c^3 & 1\end{vmatrix}\]
\[ \Rightarrow ∆ = 0\]

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पाठ 6: Determinants - Exercise 6.2 [पृष्ठ ५७]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 6 Determinants
Exercise 6.2 | Q 2.04 | पृष्ठ ५७

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