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If the second term of a GP is 2 and the sum of its infinite term is 8 , then the GP is

Options

  1. A8,2, 1 2 , 1 8 ,
  2. B10,2, 2 5 , 2 25 ,
  3. C4,2,1, 1 2 , 1 2^2 ,
  4. D6,3, 3 2 , 3 4 ,

Correct answer

C. 4,2,1, 1 2 , 1 2^2 ,

Step-by-step solution

Let the first term and common ratio of the G.P. is a and r respectively. Then, a r=2, a 1-r =8 aligned & a r r-r^2 =8 & 2=8 r-8 r^2 & 4 r^2-4 r+1=0 & r= 1 2 aligned G.P. is 4,2,1, 1 2 ,

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