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

Decide whether convergent or divergent, if convergent, find sum.

Ʃ as n = 1 and goes to infinity > (3^n + 2^n)/6^n

2. Relevant equations

a/1-r

3. The attempt at a solution

I'm just confused where to find the "r" to this without actually plugging in values for n, then dividing. For example, to get the answer (at least I think it's correct), I plugged 1 in for n, got 5/6, then i plugged in 2 for n, and got 11/36. I did (11/36) / (5/6), and used that for my r value, plugged that into a/1-r, and got about 1.31

How exactly do I find the r value? Thanks.

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# Homework Help: Finding sum to convergent series?

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