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MHT CET202122 Sep 2021Morning ShiftMathematicsMatricesActual

If A= [ array cc k & 2 -2 & - k array ] , then A ⁻¹ does not exists if k =

Options

  1. A3
  2. B2
  3. C0
  4. D1

Correct answer

B. 2

Step-by-step solution

aligned & A= [ array cc k & 2 -2 & - k array ] & | A |= [ array cc k & 2 -2 & - k array ]=- k ^2+4 aligned When - k ^2+4=0 , we get k = 2

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