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Let A = - 1 2 - 3 - 2 0 3 3 - 3 1 be a matrix, then A a d j A - 1 is equal to

Options

  1. AO 3 × 3
  2. B- 1 2 - 3 - 2 0 3 3 - 3 1
  3. CI 3
  4. D- 3 - 3 &nbsp&nbsp&nbsp1 &nbsp&nbsp&nbsp3 &nbsp&nbsp&nbsp0 - 2 - 1 &nbsp&nbsp&nbsp2 - 3

Correct answer

B. - 1 2 - 3 - 2 0 3 3 - 3 1

Step-by-step solution

We know that, A - 1 a d j   A - 1 =   A - 1 I 3 ⇒ A .   A - 1 a d j   A - 1 =   A - 1 A I 3 ⇒   a d j   A - 1 =   A - 1 A ⇒   A a d j   A - 1 =   A

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