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If X, Y, Z Are Non-zero Real Numbers, Then the Inverse of the Matrix a = ⎡ ⎢ ⎣ X 0 0 0 Y 0 0 0 Z ⎤ ⎥ ⎦ , is - Mathematics

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प्रश्न

If x, y, z are non-zero real numbers, then the inverse of the matrix \[A = \begin{bmatrix}x & 0 & 0 \\ 0 & y & 0 \\ 0 & 0 & z\end{bmatrix}\], is _____________ .

विकल्प

  • \[\begin{bmatrix}x^{- 1} & 0 & 0 \\ 0 & y^{- 1} & 0 \\ 0 & 0 & z^{- 1}\end{bmatrix}\]

  • \[xyz \begin{bmatrix}x^{- 1} & 0 & 0 \\ 0 & y^{- 1} & 0 \\ 0 & 0 & z^{- 1}\end{bmatrix}\]

  • \[\frac{1}{xyz}\begin{bmatrix}x & 0 & 0 \\ 0 & y & 0 \\ 0 & 0 & z\end{bmatrix}\]

  • \[\frac{1}{xyz} \begin{bmatrix}1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1\end{bmatrix}\]

MCQ
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उत्तर

\[\begin{bmatrix}x^{- 1} & 0 & 0 \\ 0 & y^{- 1} & 0 \\ 0 & 0 & z^{- 1}\end{bmatrix}\]
\[A = IA\]
\[ \Rightarrow \begin{bmatrix}x & 0 & 0 \\ 0 & y & 0 \\ 0 & 0 & z\end{bmatrix} = \begin{bmatrix}1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1\end{bmatrix}A\]
\[ \Rightarrow \begin{bmatrix}1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1\end{bmatrix} = \begin{bmatrix}x^{- 1} & 0 & 0 \\ 0 & y^{- 1} & 0 \\ 0 & 0 & z^{- 1}\end{bmatrix} A .................\left[\text{ Applying }R_1 = \frac{1}{x} R_1 , R_2 = \frac{1}{y} R_2\text{ and }R_3 = \frac{1}{z} R_3 \right]\]
\[ \Rightarrow A^{- 1} = \begin{bmatrix}x^{- 1} & 0 & 0 \\ 0 & y^{- 1} & 0 \\ 0 & 0 & z^{- 1}\end{bmatrix}\]

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अध्याय 7: Adjoint and Inverse of a Matrix - Exercise 7.4 [पृष्ठ ३९]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 12
अध्याय 7 Adjoint and Inverse of a Matrix
Exercise 7.4 | Q 31 | पृष्ठ ३९

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