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If a 2 − a + I = 0 , Then the Inverse of a is - Mathematics

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प्रश्न

If \[A^2 - A + I = 0\], then the inverse of A is __________ .

पर्याय

  • A2

  • A + I

  • I − A

  • A − I

MCQ
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उत्तर

I − A

\[\text{ Given: }A^2 - A + I = O\]

\[ A^{- 1} \left( A^2 - A + I \right) = A^{- 1} O ............. \left[\text{ multiplying both sides by }A^{- 1} \right]\]

\[ \Rightarrow \left( A^{- 1} A^2 \right) - \left( A^{- 1} A \right) + A^{- 1} I = O ...............\left[ \because A^{- 1} O = O \right]\]

\[ \Rightarrow A - I + A^{- 1} = O ...............\left[ \because A^{- 1} I = A^{- 1} \right]\]

\[ \Rightarrow A^{- 1} = I - A\]

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पाठ 7: Adjoint and Inverse of a Matrix - Exercise 7.4 [पृष्ठ ३८]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 7 Adjoint and Inverse of a Matrix
Exercise 7.4 | Q 20 | पृष्ठ ३८

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