Let `a_1,a_2,a_3…… ,a_n ` be in G.P such that `3a_1+7a_2 +3a_3-4a_ – InterviewSolution

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1.	Let `a_1,a_2,a_3…… ,a_n ` be in G.P such that `3a_1+7a_2 +3a_3-4a_5=0` Then common ratio of G.P can beA. 2B. `3/2`C. `5/2`D. `-1/2`
Answer» Correct Answer - B::D Given `3a_(1)+7a_(2)+3a_(3)-4a_(5)=0` `rArr7(a_(1)+a_(2)+a_(3))=4(a_(1)+a_(3)+a_(5))` `rArr7(1+r+r^(2))=4(1+r^(2)+r^(4))` `rArr7=4(r^(2)-r+1)` `rArr4r^(2)-4r+1=4` `rArr(2r-1)^(2)=4` `rArr2r-1=pm2` `rArrr=3//2,-1//2`

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