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MHT CET202310 May 2023Evening ShiftMathematicsMatricesActual

If B= [ array ccc 3 & & -1 1 & 3 & 1 -1 & 1 & 3 array ] is the adjoint of a3 3 matrix A and | A |=4 , then is equal to8

Options

  1. A1
  2. B0
  3. C-1
  4. D-2

Correct answer

A. 1

Step-by-step solution

aligned & Using | adj A|=|A|^ n -1 & But B = Adj ( A ) ...[Given] & | B |=| A |^2 & | array ccc 3 & & -1 1 & 3 & 1 -1 & 1 & 3 array |=| A |^2 & 24-4 -4=4^2 & 20-4 =16 & =1 aligned

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