(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Let an (read 'a sub n') be the nth digit after the decimal point in 2pi+2e. Evaluate

SUM (n=1 to inf) an(.1)^n

(here, again, an is meant to be 'a sub n')

2. Relevant equations

As far as I can see, this is a partial sum of a geometric series. To find the nth partial sum (or, in other words the infinite sum) use a/(1-r) where a is the first term of the series (scalar multiple) and r is the ratio of the exponent of the general form for geo series: ar^n

3. The attempt at a solution

My attempt gave back to sn=1/9

I used: .1/1-.1

I guess I'm thinking about this incorrectly

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# Homework Help: Partial Sums

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