# Determining Divergence or Convergence in Series

1. Nov 22, 2008

### badirishluck

1. The problem statement, all variables and given/known data
$$\sum$$ (2n$$^{2}$$+3n)$$/\sqrt{5+n^{5}}$$
index n=1 to infinity

2. Relevant equations

3. The attempt at a solution
I tried both the Ratio Test (limit as n goes to infinity of a$$_{n+1}$$$$/a_{n}$$) and the Limit comparison test (limit as n goes to infinity of $$a_{n}$$/ $$b_{n}$$) but wasn't able to come up with the same answer from the two tests. What am I doing wrong?
Does it converge or diverge? How?
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Nov 22, 2008

### LogicalTime

try breaking it into 2 pieces and see what you can do with the individual pieces, see if
$$\sum$$ (2n$$^{2}$$)$$/\sqrt{5+n^{5}}$$
converges, if it does then the whole thing does since the 2nd term is smaller, if it doesn't then the whole thing does not converge.

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