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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 &nbsp&nbsp&nbsp2 - 3 - 2 &nbsp&nbsp&nbsp0 &nbsp&nbsp&nbsp3 &nbsp&nbsp&nbsp3 - 3 &nbsp&nbsp&nbsp1
  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 &nbsp&nbsp&nbsp2 - 3 - 2 &nbsp&nbsp&nbsp0 &nbsp&nbsp&nbsp3 &nbsp&nbsp&nbsp3 - 3 &nbsp&nbsp&nbsp1

Step-by-step solution

A a d j A - 1 = ? 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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