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If A = 1 - 2     1 2     λ - 2 1     3 - 3 be the adjoint matrix of matrix B such that B = 9 , then the value of λ is equal to

Options

  1. A1
  2. B- 77 4
  3. C23 2
  4. D- 39 2

Correct answer

B. - 77 4

Step-by-step solution

A = a d j B A = B 2 1 - 2 1 2 λ - 2 1 3 - 3 = 8 1 ⇒ 1 - 3 λ + 6 + 2 - 6 + 2 + 1 6 - λ = 8 1 ⇒ - 4 λ + 4 = 8 1 ⇒ λ = - 77 4

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