# Thread: Absolute and conditional convergence

1. ## Absolute and conditional convergence

infinity over sigma n=1 (-1)^n*n^4/n^3+1 Find if the series converges absolutely or not at all.

2. Originally Posted by Link88
infinity over sigma n=1 (-1)^n*n^4/n^3+1 Find if the series converges absolutely or not at all.
do you mean $\sum_{n = 1}^\infty \frac {(-1)^n n^4}{n^3 + 1}$??

consider this: $\lim_{n \to \infty} \frac {n^4}{n^3 + 1} = \infty$

3. what test should i use to show this?

4. Originally Posted by Link88
what test should i use to show this?
The fact that $| a_n | \not \rightarrow 0$ should be a pretty good clue I would have thought ....