# calculus

How do I find the sum of a geometric series from 2 to infinity of -3/ (4^n) ?

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asked by tom
1. a = -3/4
r = 1/4
S(2..∞) = S∞ - S1

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posted by oobleck
2. so s=-13/4?

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posted by tom
3. no it should be -1/4

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posted by tom

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