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If A = 2 - 3 - 4 1 , then Adj 3 A 2 + 12 A is equal to:

Options

  1. A72 - 84 - 63 51
  2. B51 63 84 72
  3. C51 84 63 72
  4. D72 - 63 - 84 51

Correct answer

B. 51 63 84 72

Step-by-step solution

Given, A = 2 - 3 - 4 1 ⇒   A 2 = 2 - 3 - 4 1   2 - 3 - 4 1 ⇒   A 2 = 4 + 12 - 6 - 3 - 8 - 4 12 + 1 ⇒   A 2 = 16 - 9 - 12 13 ⇒   3 A 2 = 48 - 27 - 36 39 and 12 A = 24 - 36 - 48 12 ∴   3 A 2 + 12 A = 72 - 63 - 84 51 Adj 3 A 2 + 12 A = 51 84 63 72 T = 51 63 84 72

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