An infinite `G.P.` has `2^(nd)` term `x` and its sum is `4`. Then `x` – InterviewSolution

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1.	An infinite `G.P.` has `2^(nd)` term `x` and its sum is `4`. Then `x` belongs toA. `(0,2]`B. `(1,8)`C. `(-8,1]`D. none of these
Answer» Correct Answer - C `(c )` `"Sum"=((x)/(r ))/(1-r)=4` (where `r` is common ratio) `x=4r(1-r)` `=4(r-r^(2))` For `r in (-1,1)` `r-r^(2)in(-2,(1)/(4)]` `impliesx in (-8,1]`

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