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If A, B Are Two N × N Non-singular Matrices, Then - Mathematics

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प्रश्न

If A, B are two n × n non-singular matrices, then __________ .

विकल्प

  • AB is non-singular

  • AB is singular

  • \[\left( AB \right)^{- 1} A^{- 1} B^{- 1}\]

  • (AB)−1 does not exist

MCQ
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उत्तर

AB is non-singular

A and B are non - singular matrices of order n × n.
\[ \therefore \left| A \right| \neq 0\text{ and }\left| B \right| \neq 0 . . . \left( 1 \right)\]

A and B are of the same order, so AB is defined and is of the same order .

Thus, 
\[\left| AB \right| = \left| A \right|\left| B \right| \]
\[ \Rightarrow \left| AB \right| \neq 0 \left[\text{ Using }\left( 1 \right) \right] \]
Thus, AB is non - singular . 

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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 6 | पृष्ठ ३७

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