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MHT CET202123 Sep 2021Evening ShiftMathematicsMatricesActual

If A = [ array cc 2 & 3 5 & -2 array ] and A ⁻¹= KA , then K is

Options

  1. A19
  2. B-1 19
  3. C-19
  4. D1 19

Correct answer

D. 1 19

Step-by-step solution

aligned & A= [ array cc 2 & 3 5 & -2 array ] & |A|-4-15=-19 and adj A= [ array cc -2 & -3 -5 & 2 array ] & A⁻¹= -1 19 [ array cc -2 & -3 -5 & 2 array ]= 1 19 [ array cc 2 & 3 5 & -2 array ] k = 1 19 aligned

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