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AP EAMCET202421 May 2024Evening ShiftMathematicsMatricesActual

Assertion (A): If B is a 3 3 matrix and |B|=6 , then | Adj (B)|=36 Reason (R): If B is a square matrix of order n , then | Adj (B)|=|B|^ n

Options

  1. ABoth (A) and (R) are true and (R) is the correct explanation of (A)
  2. BBoth (A) and (R) are true but (R) is not the correct explanation of (A)
  3. C(A) is true but (R) is false
  4. D(A) is false but (R) is true

Correct answer

C. (A) is true but (R) is false

Step-by-step solution

|B|=6 | Adj (B)|=6³⁻¹=36 Since |B_ n n |=k | Adj (B)|=k^ n -1 .

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