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If three positive numbers a , b and c are in A.P. such that a b c = 8 , then the minimum possible value of b is:

Options

  1. A4 2 3
  2. B2
  3. C4 1 3
  4. D4

Correct answer

B. 2

Step-by-step solution

As a + c = 2 b , Using A . M ≥ G . M ⇒ a + b + c 3 ≥ a b c 1 3   ⇒ 3 b 3 ≥ 8 1 3 b ≥ 2   ∴   b m i n = 2

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