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MHT CET20192 May 2019Morning ShiftMathematicsMatricesActual

If A is non-singular matrix such that A - 2 I A - 4 I = 0 , then A + 8 A - 1 = ________

Options

  1. AI
  2. B0
  3. C3 I
  4. D6 I

Correct answer

D. 6 I

Step-by-step solution

Given: A is non-singular matrix then A ≠ 0 Also A - 2 I A - 4 I = 0 A 2 - 6 A + 8 I = 0 m u l t i p l y b y A – 1 both the side W e h a v e A + 8 A - 1 = 6 I

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