Summing an infinite series question

TheRascalKing
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Homework Statement



I need to fin the sum of the following two infinite series:
1. Ʃ[n=0 to ∞] ((2^n + 3^n)/6^n)

and 2. Ʃ[n=2 to ∞] (2^n + (3^n / n^2)) (1/3^n)

Homework Equations



use the sum Ʃ[n=2 to ∞] (1/n^2) = ∏^2 / 6 as necessary

The Attempt at a Solution



I tried to manipulate them both to make them geometric or telescoping, to no avail. It seems like neither series is telescoping or geometric, so isn't it impossible to definitively sum them?

I started to sum them by adding their partial sums, but they converge very slowly and it would take hundreds of calculations to provide enough evidence for the sums.
 
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Hint:

1. Split them into two rational expressions. Simplify (ask what is ##\frac{a^n}{b^n}##?)

2. Multiply the bracket out. Simplify.

It's all just algebra.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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