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If A= [ array ccc 1 & -2 & 2 0 & 2 & -3 3 & -2 & 4 array ] , then A adj (A) is equal to

Options

  1. A[ array lll 5 & 0 & 0 0 & 5 & 0 0 & 0 & 5 array ]
  2. B[ array lll 5 & 1 & 1 1 & 5 & 1 1 & 1 & 5 array ]
  3. C[ array lll 0 & 0 & 0 0 & 0 & 0 0 & 0 & 0 array ]
  4. D[ array lll 8 & 0 & 0 0 & 8 & 0 0 & 0 & 8 array ]

Correct answer

D. [ array lll 8 & 0 & 0 0 & 8 & 0 0 & 0 & 8 array ]

Step-by-step solution

We have, aligned A &= [ array ccc 1 & -2 & 2 0 & 2 & -3 3 & -2 & 4 array ] |A| &= [ array ccc 1 & -2 & 2 0 & 2 & -3 3 & -2 & 4 array ] &=1[8-6]+3[6-4]=2+6=8 aligned Now, we know that A ( adj A)=8 l= [ array lll 8 & 0 & 0 0 & 8 & 0 0 & 0 & 8 array ]

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