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If A5 = O Such that a N ≠ I for 1 ≤ N ≤ 4 , Then ( I − a ) − 1 (A) A4 (B) A3 (C) I + a (D) None of These - Mathematics

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प्रश्न

If A5 = O such that \[A^n \neq I\text{ for }1 \leq n \leq 4,\text{ then }\left( I - A \right)^{- 1}\] equals ________ .

विकल्प

  • A4

  • A3

  • I + A

  • none of these

MCQ
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उत्तर

None of these

\[I - A^5 = \left( I - A \right)\left( I + A + A^2 + A^3 + A^4 \right)\]

Now,

\[ A^5 = 0\]

\[ \Rightarrow I = \left( I - A \right)\left( I + A + A^2 + A^3 + A^4 \right)\]

\[ \Rightarrow \frac{I}{\left( I - A \right)} = \left( I + A + A^2 + A^3 + A^4 \right)\]

\[ \Rightarrow \left( I - A \right)^{- 1} = I + A + A^2 + A^3 + A^4\]

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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 11 | पृष्ठ ३७

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