Proving series is convergent/divergent

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Homework Statement



The problem is proving that the following series is convergent or divergent:


Ʃ 1 / [(n)(n+1)(n+2)]^(1/3)
n=1

Homework Equations



The limit or direct comparison test

The Attempt at a Solution



lim {1 / [(n)(n+1)(n+2)]^(1/3)} / (1/n)
n->∞

I then attempted to simplify this and use l'Hopital's Rule, but the cube root made it too complicated, and I couldn't come to an answer.
 
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abcde149149 said:

Homework Statement



The problem is proving that the following series is convergent or divergent:


Ʃ 1 / [(n)(n+1)(n+2)]^(1/3)
n=1

Homework Equations



The limit or direct comparison test

The Attempt at a Solution



lim {1 / [(n)(n+1)(n+2)]^(1/3)} / (1/n)
n->∞

I then attempted to simplify this and use l'Hopital's Rule, but the cube root made it too complicated, and I couldn't come to an answer.

l'Hopital is serious overkill. (n)(n+2)(n+2)=n^3(1)(1+1/n)(n+2/n). Try simplifying.
 
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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