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If a is a Non-singular Symmetric Matrix, Write Whether A−1 is Symmetric Or Skew-symmetric. - Mathematics

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प्रश्न

If A is a non-singular symmetric matrix, write whether A−1 is symmetric or skew-symmetric.

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उत्तर

\[\text{ Let A be an invertible symmetric matrix . Then, }\]
\[ \left| A \right| \neq 0\text{ and }A^T = A\]
\[\text{ Now, }\left( A^{- 1} \right)^T = \left( A^T \right)^{- 1} \]
\[ \Rightarrow \left( A^{- 1} \right)^T = A^{- 1} [ \because A^T = A]\]
\[\text{ Thus, }A^{- 1}\text{ is symmetric matrix .}\]

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पाठ 7: Adjoint and Inverse of a Matrix - Exercise 7.3 [पृष्ठ ३५]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 7 Adjoint and Inverse of a Matrix
Exercise 7.3 | Q 15 | पृष्ठ ३५

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