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

Find a closed form for the nth partial sum, and determine whether the series converges by calculating the limit of the nth partial sum.

1. 2+2/5 + 2/25+.....2/5^{k-1}

2. Relevant equations

3. The attempt at a solution

What I did was I found out it was a geometric sequence.

with R = .2

s_{n}=2+2/5+2/25+2/5^{n-1}

.2s_{n}= 2/5+2/25+2/125+2/5^{n}

I subtract the equations giving me

.8s^{n}=2+2/5_{n}

I divide .8 to both sides giving me

s_{n}= 5/2+1/2^{n}

I know I am messing up with the multiplication / subtraction of the Nth term much help is appreciated (:

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# Homework Help: Find a closed form for the nth partial sum, and determine whether the series converge

Can you offer guidance or do you also need help?

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