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If A= [ array lll a & 0 & 0 0 & a & 0 0 & 0 & a array ] , then |A|| adj A is equal to

Options

  1. Aa^9
  2. Ba⁻⁹
  3. C-a^9
  4. D2a^9

Correct answer

A. a^9

Step-by-step solution

A is a 3 3 diagonal matrix |A| = a a a = a^3 Using the property: |A|| adj ,A| = |A|^n for an n n matrix: |A|| adj ,A| = |A|^3 = (a^3)^3 = a^9 Correct option: (1)

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