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The inverse of a matrix A is given by [ array cc -2 & 1 3 2 & - 1 2 array ] What is A equal to?

Options

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

Correct answer

A. [ array ll 1 & 2 3 & 4 array ]

Step-by-step solution

aligned & A= (A⁻¹ )⁻¹= 1 (-2 - 1 2 -1 3 2 ) [ array ll - 1 2 & -1 - 3 2 & -2 array ] & =-2 [ array ll - 1 2 & -1 - 3 2 & -2 array ]= [ array ll 1 & 2 3 & 4 array ] aligned

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