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Paragraph: Let S_r, r N , denote the sum of an infinite GP whose first term is 2 r-1 and common ratio 1 2 r . Let V_n= _ r=1 ^n S_r and Q_n= _ r=1 ^n 1 S_r S_ r+1 Question: _ n V_n n^2 equals

Options

  1. A0
  2. B-1
  3. C1
  4. D2

Correct answer

C. 1

Step-by-step solution

aligned & V_n= _ r=1 ^n S_r=2 _ r=1 ^n r=n(n+1) & _ n V_n n^2 = _ n n+1 n =1 aligned

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