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MHT CET2019Evening ShiftMathematicsMatricesActual

If is non-singular matrix and A + l A - l = 0 then A + A - 1 = … …

Options

  1. A2A
  2. B0
  3. Cl
  4. D3 l

Correct answer

A. 2A

Step-by-step solution

We have, A is non-singular matrix ∴ A = 0 and A + l A - l = 0 ⇒ A 2 - l 2 = 0 ⇒ A 2 = l 2 = l ⇒ A . A = l ⇒ A - 1 = A ∴ A + A - 1 = A + A = 2 A

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