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MHT CET202310 May 2023Morning ShiftMathematicsMatricesActual

If B= [ array lll 1 & & 2 1 & 2 & 2 2 & 3 & 3 array ] is the adjoint of a 3 3 matrix A and | A |=5 , then is equal to

Options

  1. A25
  2. B27
  3. C3 3
  4. D5

Correct answer

B. 27

Step-by-step solution

Using | Adj A|=|A|^ n-1 But B = Adj ( A ) ...['Given] | B |=| A |^2 aligned & | array lll 1 & & 2 1 & 2 & 2 2 & 3 & 3 array |=| A |^2 & -2=5^2 & -2=25 & =27 aligned

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