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KCET2022MathematicsMatrices

If A is a 3 3 matrix such that |5 adj A|=5 , then |A| is equal to

Options

  1. A1
  2. B1 / 25
  3. C1 / 5
  4. D5

Correct answer

C. 1 / 5

Step-by-step solution

Given, A is a 3 3 matrix and |5 Adj (A)|=5 aligned & |5 adj (A)|=5 5^3| adj (A)|=5 & | adj (A)|= 1 5^2 |A|³⁻¹= 1 5^2 & |A|^2= ( 1 5 )^2 |A|= 1 5 aligned

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