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Show that the ratio of the sum of first n terms of a G.P. to the sum of terms from `(n+1)^(t h)` to `(2n)^(t h)` term is `1/(r^n)` . 9873740001

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The correct Answer is:
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`S_(n)=(a(1-r^(n)))/(1-r)`
Sum from (n+1)th term to (2n)th term
`s_(n)=S_(2n)-S_(n)`
`=(a(1-r^(2n)))/(1-r)-(a(1-r^(n)))/(1-r)=(ar^(n)(1-r)^(n)))/(1-r)`
`Now (S_(n))/(s_(n))=((a(1-r^(n)))/(1-r))/((ar^(n)(1-r^(n)))/(1-r))`
`implies (S_(n))/(s_(n))=(1)/(r_(n))" "` Hence Proved.
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NAGEEN PRAKASHAN ENGLISH-SEQUENCE AND SERIES-Exercise 9.3
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  12. Show that the ratio of the sum of first n terms of a G.P. to the su...

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  17. If A and G be A.M. and GM., respectively between two positive numbers...

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