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Sequences and Series

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Question 57

A geometric series is a+ar+ar2+…a + ar + ar^2 + \dotsa+ar+ar2+…

Prove that the sum of the first n n\,n terms of the series is

Sn=a(1−rn)1−r S_n = \frac{a(1-r^n)}{1-r} Sn​=1−ra(1−rn)​
[4]

Sequences and Series Questions

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