# divergence of a sequence

• Dec 3rd 2009, 09:10 AM
xalk
divergence of a sequence
Prove ,by using the ε-definition, that the sequence :

$S_{n} = (-1)^n$ diverges
• Feb 13th 2010, 01:52 PM
felper
Quote:

Originally Posted by xalk
Prove ,by using the ε-definition, that the sequence :

$S_{n} = (-1)^n$ diverges

The ε-definition proves that some number L is the limit of a sequence. I've never heard that one can prove that a sequences diverges using that definition. We can prove that some number L is not the limit of the sequence, buy i've no idea of how can i use that definition to prove the divergence. Can you give me some hint?
• Feb 13th 2010, 02:55 PM
CaptainBlack
Have you read the sticky at the top opf this forum?

CB