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If A is a singular matrix, then adj A is ______. - Mathematics

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प्रश्न

If A is a singular matrix, then adj A is ______.

विकल्प

  • non-singular

  • singular

  • symmetric

  • not defined

MCQ
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उत्तर

If A is a singular matrix, then adj A is singular.

\[\text{ A is singular, so } \left| A \right| = 0\].

By definition, we have

A \[adj \left( A \right) = O \]

\[ \Rightarrow \left| A adj \left( A \right) \right| = \left| O \right|\]

\[ \Rightarrow \left| A \right| \left| adj \left( A \right) \right| = 0 \]

\[ \Rightarrow \left| adj \left( A \right) \right| = 0 \]

\[\text{ Hence, }adj \left( A \right)\text{ is singular}\].

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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 5 | पृष्ठ ३७

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