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Paragraph: Let A= [ array lll 3 & -3 & 4 2 & -3 & 4 0 & -1 & 1 array ] Question: What is A( adj A) equal to?

Options

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

Correct answer

D. [ array lll 1 & 0 & 0 0 & 1 & 0 0 & 0 & 1 array ]

Step-by-step solution

We have : A= [ array lll 3 & -3 & 4 2 & -3 & 4 0 & -1 & 1 array ] So, Determinant aligned & |A|=3(-3+4)-2(-3+4)+0=3-2=1 & A( adj A)=|A| I=1 . I=I . aligned Option (d) is correct option.

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