# math

Does the series converge or diverge? If it converges, what is the sum? Show your work.

∑∞n=1−4(−12)n−1

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1. if you don't have any fractions, there's no way it will converge
maybe you have some exponents? Use ^ if so
and also parentheses

what you have, as written, is just some multiple of n
Also, if you want to sum from 1 to ∞, maybe something like ∑(1..∞)

In other words, write something that makes sense.

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oobleck
2. the fraction is -1/2

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3. well,

∑ (-1/2)^n = -1/3
n=1

because it's just a geometric series with
a = -1/2
r = -1/2

I know that's not exactly what you have, but it should not be hard to adapt it.

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oobleck

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