# Convergent, conditionally convergent or divergent. Need help with this please.

• Jan 19th 2010, 08:08 AM
alpha
Convergent, conditionally convergent or divergent. Need help with this please.
Investigate whether the series ∑_(n =1) to ∞ of [(-1)^(n+1)]/√n is absolutely convergent, conditionally convergent or divergent.

All help appreciated. Thanks.
• Jan 19th 2010, 08:13 AM
Drexel28
Quote:

Originally Posted by alpha
Investigate whether the series ∑_(n =1) to ∞ of [(-1)^(n+1)]/√n is absolutely convergent, conditionally convergent or divergent.

All help appreciated. Thanks.

This is pretty straightforward. Does the series itself converge? Does the series still converge if you take the absolute value of the summand?
• Jan 19th 2010, 08:23 AM
alpha
I have no idea about this. I am no good at series and cant asnwer this question.

Thanks.
• Jan 19th 2010, 08:44 AM
Krizalid
You were told what to do, and I would've answered as Drexel28 did.
• Jan 19th 2010, 09:02 AM
alpha
How do i work out whether this series converges? As I told, I am no good at this topic so am struggling on how to tackle this question.
• Jan 19th 2010, 09:54 AM
Krizalid