Show Cauchy Sequence iff Subsequence is Quasi-Cauchy

[MQ3533]

Quasi-Cauchy help!

Show that a sequence is Cauchy iff every subsequence is quasi-Cauchy?


A sequence (xn) is called a quasi-Cauchy sequence if for all epsilon greater than 0 there exists N such that |xn+1 − xn| < epsilon.


Help please...

 

[hgfalling]

Hi, we'll be happy to help you iron out problems with your proof, or provide hints in the right direction...but first you have to show us what you've done already.