I'm basically trying to show that if (a(adsbygoogle = window.adsbygoogle || []).push({}); _{n}) and (b_{n}) are Cauchy sequences, then (c_{n}) = |a_{n}- b_{n}| is also a Cauchy sequence.

I know that the triangle inequality is going to be used at one point or another, but I suppose I'm a little confused because:

(a_{n}) is Cauchy implies |a_{n}- a_{m}| < e

(b_{n}) is Cauchy implies |b_{n}- b_{m}| < e

I think at some point my e's are going to be changed to e/2, which is totally legitimate because e is arbitrary anyway.

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# Cauchy Sequence

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