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The sum of the series formed by the sequence 3 , 3 , 1, upto infinity is:

Options

  1. A3 3 ( 3 +1) 2
  2. B3 3 ( 3 -1) 2
  3. C3( 3 +1) 2
  4. D3( 3 -1) 2

Correct answer

A. 3 3 ( 3 +1) 2

Step-by-step solution

3, 3 , 1, are in G.P. Here, a=3 , and r= 1 3 Sum of infinity terms aligned & = a 1-r = 3 1- 1 3 = 3 3 -1 3 & = 3 3 3 -1 3 +1 3 +1 = 3 3 ( 3 +1) 3-1 & = 3 3 ( 3 +1) 2 aligned

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