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What is the geometric mean of the sequence 1,2,4,8 , .........., 2^n ?

Options

  1. A2^ n / 2
  2. B2^ (n+1) / 2
  3. C2^ (n+1) -1
  4. D2^ (n-1)

Correct answer

B. 2^ (n+1) / 2

Step-by-step solution

We know that geometric mean of a₁, a₂, a₃, . . . a_n is (a₁ a₂ a₃ . . . a_n )^ 1 / n =2^ n(n+1) 2 1 n =2^ n+1 2 .

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