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MHT CET20226 Aug 2022Morning ShiftMathematicsMatricesActual

If A= [ array cc 2 & -3 -4 & 1 array ] , then adj (3 A^2+12 A ) is equal to

Options

  1. A[ array cc 72 & -63 -84 & 51 array ]
  2. B[ array ll 51 & 63 84 & 72 array ]
  3. C[ array cc 72 & -84 -63 & 51 array ]
  4. D[ array ll 51 & 84 63 & 72 array ]

Correct answer

B. [ array ll 51 & 63 84 & 72 array ]

Step-by-step solution

aligned & adj (3 ~A ^2+12 ~A )= adj 3 ~A ( ~A +4 I ) & = adj ( A +4 I ) adj (3 ~A ) & = adj ( [ array cc 6 & -3 -4 & 5 array ] ) adj ( [ array cc 6 & -9 -12 & 3 array ] ) & = [ array ll 5 & 3 4 & 6 array ] [ array cc 3 & 9 12 & 6 array ] & = [ array ll 51 & 63 84 & 72 array ] aligned

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