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MHT CET20225 Aug 2022Evening ShiftMathematicsMatricesActual

If A= [ array ccc 1 & 3 & -2 -3 & 0 & -5 2 & 5 & 0 array ] and A( adj A)=K I , then the value of K is (where I is unit matrix of order 3)

Options

  1. A-25
  2. B25
  3. C85
  4. D-85

Correct answer

B. 25

Step-by-step solution

A( adj A)=|A| . I Hence K =| A |=25

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