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If B Is a Non-singular Matrix And A Is a Square Matrix, Then Det (B−1 Ab) is Equal to - Mathematics

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प्रश्न

If B is a non-singular matrix and A is a square matrix, then det (B−1 AB) is equal to ___________ .

विकल्प

  • Det (A−1)

  • Det (B−1)

  • Det (A)

  • Det (B)

MCQ
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उत्तर

Det (A)

B is non - singular.

\[\text{ This implies that }\left| B \right| \neq 0,\text{ that B is invertible and that }B^{- 1}\text{ exists }. \]

Here, B is invertible .

\[ \therefore \left| B^{- 1} \right| = \left| B \right|^{- 1} = \frac{1}{\left| B \right|}\]

\[ \Rightarrow \left| B^{- 1} AB \right| = \left| B^{- 1} \right|\left| AB \right|\]
\[ \Rightarrow \left| B^{- 1} AB \right| = \left| B \right|^{- 1} \left| A \right|\left| B \right| \]
\[ \Rightarrow \left| B^{- 1} AB \right| = \frac{1}{\left| B \right|}\left| A \right|\left| B \right| \]
\[ \Rightarrow \left| B^{- 1} AB \right| = \left| A \right|\]

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 7: Adjoint and Inverse of a Matrix - Exercise 7.4 [पृष्ठ ३७]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 7 Adjoint and Inverse of a Matrix
Exercise 7.4 | Q 9 | पृष्ठ ३७

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