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MHT CET202014 Oct 2020Evening ShiftMathematicsMatricesActual

If A= [ array ccc 0 & 0 & -1 0 & -1 & 0 -1 & 0 & 0 array ] , then

Options

  1. AA is not invertible
  2. BA=A⁻¹
  3. CA⁻¹=2 A
  4. DA⁻¹=I

Correct answer

B. A=A⁻¹

Step-by-step solution

Here | A |=-1(-1)=1 and A⁻¹= [ array ccc 0 & 0 & -1 0 & -1 & 0 -1 & 0 & 0 array ]=A

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