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If for the Matrix A, A3 = I, Then A−1 = - Mathematics

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प्रश्न

If for the matrix A, A3 = I, then A−1 = _____________ .

विकल्प

  • A2

  • A3

  • A

  • none of these

MCQ
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उत्तर

A2
\[\text{ Given: }\hspace{0.167em} A^3 = I \]
\[ \Rightarrow A^3 A^{- 1} = I A^{- 1}.......... \left[\text{Multiplying both sides by }A^{- 1} \right]\]
\[ \Rightarrow A^2 = A^{- 1}\]

 

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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 13 | पृष्ठ ३७

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