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how 2 solve dis...?? 1+(1+(1/2))+(1+(1/2)+(1/4))+.......to n terms plz ...plz ...tell me dis..
how 2 solve dis...??
1+(1+(1/2))+(1+(1/2)+(1/4))+.......to n terms
plz ...plz ...tell me dis..
Dear srishtisum of nterms can be written as as n+n-1/2 + n-2/4-----+1/2n-1which is sum of nterms of an AGPThe sum Sn of first n terms of an A.G. P. is obtained in the following way : Sn = ab + (a + d)br + (a + 2d)br2 +.........+(a + (n - 2)d)brn-2 + (a + (n - 1)d)brn-1 Multiply both sides by r, so that r Sn = abr + (a + d)br2+.........+(a + (n - 3)d)brn-2 + (a + (n - 2)d)brn-1 + (a + (n - 1)d)brn Subtracting, we get (1 - r)Sn = ab + dbr + dbr2 +.......+dbrn - 2 + dbrn - 1 - (a + (n - 1)d)brn = ab + dbr/(1–rn–1)/(1–r) – (a+(n–1)d)brn => Sn = ab/1–r + dbr(1–rn–1)/(1–r)2 – (a+(n–1)d)brn/1–r a=n b=1 r=.5 d=-1 So Sn = 2n+(-1)*0.5*1(1-0.5n-1)*4-2n =>Sn = 2n-2(1-0.5n-1)-2n Please feel free to post as many doubts on our discussion forum as you can.we will get you the answer and detailed solution very quickly.All the best. Regards,Askiitians ExpertsPrudhvi Teja Now you can win exciting gifts by answering the questions on Discussion Forum. So help discuss any query on askiitians forum and become an Elite Expert League askiitian
Dear srishtisum of nterms can be written as as n+n-1/2 + n-2/4-----+1/2n-1which is sum of nterms of an AGPThe sum Sn of first n terms of an A.G. P. is obtained in the following way : Sn = ab + (a + d)br + (a + 2d)br2 +.........+(a + (n - 2)d)brn-2 + (a + (n - 1)d)brn-1 Multiply both sides by r, so that r Sn = abr + (a + d)br2+.........+(a + (n - 3)d)brn-2 + (a + (n - 2)d)brn-1 + (a + (n - 1)d)brn Subtracting, we get (1 - r)Sn = ab + dbr + dbr2 +.......+dbrn - 2 + dbrn - 1 - (a + (n - 1)d)brn = ab + dbr/(1–rn–1)/(1–r) – (a+(n–1)d)brn => Sn = ab/1–r + dbr(1–rn–1)/(1–r)2 – (a+(n–1)d)brn/1–r a=n
b=1
r=.5
d=-1
So Sn = 2n+(-1)*0.5*1(1-0.5n-1)*4-2n
=>Sn = 2n-2(1-0.5n-1)-2n
Please feel free to post as many doubts on our discussion forum as you can.we will get you the answer and detailed solution very quickly.All the best. Regards,Askiitians ExpertsPrudhvi Teja Now you can win exciting gifts by answering the questions on Discussion Forum. So help discuss any query on askiitians forum and become an Elite Expert League askiitian
Please feel free to post as many doubts on our discussion forum as you can.we will get you the answer and detailed solution very quickly.All the best.
Regards,Askiitians ExpertsPrudhvi Teja
Now you can win exciting gifts by answering the questions on Discussion Forum. So help discuss any query on askiitians forum and become an Elite Expert League askiitian
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