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

Ʃ((x-3)^(n)) / (n*2^(n))

2. Relevant equations

lim as n→ ∞ (An+1 / An)

3. The attempt at a solution

When dividing two fractions, invert the second and multiple to get what you see below.

(x-3)^(n+1)/((n+1)*2^(n+1)) * (n*2^(n))/((x-3)^(n))

Do some cross canceling to get (n(x-3)) / (2(n-1))

Then when you take the limit as n goes to infinity, you're just left with (x-3)/2

What I'm stuck on is what to do next. The answer is two, but I'm not seeing it.

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# Homework Help: Using ratio test to find radius of convergence

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