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Apr 2 2015 08:09am
So, for some sequence X, to prove lim(X) = L I have to prove | Xn - L | < ε for all ε > 0 and n > M

So, if Xn is hard to work with, am I really just trying to find a sequence Y such that Yn > Xn, and | Yn - L | < ε ?

My professor was talking about finding a "middle ground" sequence but I tuned him out.
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Apr 2 2015 12:16pm
There are different patterns where you can use another sequence Y instead of X.
The best is to post here your exact sequence X, so anybody could give you some tips around it.

Quote (Mastersam93 @ Apr 2 2015 03:09pm)
So, for some sequence X, to prove lim(X) = L I have to prove | Xn - L | < ε for all ε > 0 and n > M
(...)


Notice this exact phrasing for X to tend towards L :

for all ε > 0, a rank M exists such that | Xn - L | < ε for all n > M

It must be clear that M depends on ε.
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Apr 3 2015 02:06am
Quote (feanur @ Apr 2 2015 01:16pm)
It must be clear that M depends on ε.


This is the best advice.
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