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If x 2 + x x + 1 x - 2 2 x 2 + 3 x - 1 3 x 3 x - 3 x 2 + 2 x + 3 2 x - 1 2 x - 1 = a x - 12 , then a is equal to:

Options

  1. A- 24
  2. B24
  3. C- 12
  4. D12

Correct answer

B. 24

Step-by-step solution

Put x = 1 on both the sides 2 2 - 1 4 3 0 6 1 1 = a - 12 ⇒ 2 3 - 0 - 2 4 - 0 - 1 4 - 18 = a - 12 ⇒ 6 - 8 + 14 = a - 12 ⇒ 12 = a - 12 ⇒ 24 = a .

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