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MHT CET20226 Aug 2022Evening ShiftMathematicsMatricesActual

If A= [ array lll 1 & 2 & 1 3 & 1 & 3 array ] and B= [ array ll 2 & 3 1 & 2 1 & 2 array ] , then (A B)⁻¹=

Options

  1. A[ array cc -17 5 & 9 5 2 & -1 array ]
  2. B[ array cc 17 5 & 9 5 2 & 1 array ]
  3. C[ array cc -17 5 & 2 -9 5 & -1 array ]
  4. D[ array cc -17 5 & 2 9 5 & 1 array ]

Correct answer

A. [ array cc -17 5 & 9 5 2 & -1 array ]

Step-by-step solution

aligned & A B= [ array ll 2+1+1 & 3+4+2 6+1+3 & 9+2+6 array ] & = [ array cc 5 & 9 10 & 17 array ] & (A B)-1= 1 -5 [ array cc 17 & -9 -10 & 5 array ]= [ array cc - 17 5 & 9 5 2 & -1 array ] aligned

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