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MHT CET20227 Aug 2022Morning ShiftMathematicsMatricesActual

If matrix A = [ array ll 1 & 2 4 & 3 array ] is such that AX = I , where I is 2 2 unit matrix, then X=

Options

  1. A1 5 [ array ll -3 & -2 -4 & -1 array ]
  2. B1 5 [ array cc -3 & 2 4 & -1 array ]
  3. C1 5 [ array ll 3 & 2 4 & 1 array ]
  4. D1 5 [ array cc 3 & -2 -4 & 1 array ]

Correct answer

B. 1 5 [ array cc -3 & 2 4 & -1 array ]

Step-by-step solution

AX = I X = A ⁻¹= A ⁻¹ X= [ array ll 1 & 2 4 & 3 array ]⁻¹= -1 5 [ array cc 3 & -2 -4 & 1 array ]= 1 5 [ array cc -3 & 2 4 & -1 array ]

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