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If A and B are square matrices of order 3 such that A = 3 and B = 2 , then the value of A - 1 a d j B - 1 a d j 3 A - 1 is equal to

Options

  1. A27
  2. B27 4
  3. C1 108
  4. D1 4

Correct answer

B. 27 4

Step-by-step solution

A - 1 a d j B - 1 a d j 3 A - 1 = A - 1 a d j B - 1 a d j 3 A - 1 = 1 A B - 1 2 × 3 A - 1 2 = 1 A × 1 B 2 × 3 6 A 2 = 3 6 3 3 × 2 2 = 27 4

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