Help with proving a sequence converges

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Homework Help Overview

The discussion revolves around proving the convergence of a sequence, specifically showing that if the limit of one sequence \( s_n \) is \( L \) and the limit of the difference between two sequences \( |s_n - t_n| \) approaches 0, then the limit of the second sequence \( t_n \) must also be \( L \.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the implications of the limits given and explore the relationship between the sequences. Some raise questions about the application of the epsilon-delta definition of limits and how it relates to the absolute differences between the sequences.

Discussion Status

There are multiple lines of reasoning being explored, with some participants attempting to clarify the conditions under which the convergence can be proven. Hints and suggestions for approaching the proof have been provided, but no consensus has been reached on the method to be used.

Contextual Notes

Participants express uncertainty about the application of the absolute value in the context of limits and the necessary conditions for proving convergence. There is also a mention of a potential duplicate thread, indicating some confusion in the discussion.

jarvegg
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I am really stuck on this on

Let sn and tn be sequences. Suppose that lim sn = L (where s is a real number) and lim |sn - tn| = 0. Prove that lim tn = L.

I think this is going in the right way but i am not sure. If the lim an = A, then lim |an - A| = 0.

any help would be very nice.
 
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Help proving a sequesnce converges

I am really stuck on this on

Let sn and tn be sequences. Suppose that lim sn = L (where s is a real number) and lim |sn - tn| = 0. Prove that lim tn = L.

I think this is going in the right way but i am not sure. If the lim an = A, then lim |an - A| = 0.

any help would be very nice.
 
let N be so large that
|s_n|<epsilon/2
|s_n-t_n|<epsilon
what can you say about
|t_n|
?
hint
|A-B|<=|A|+|B|
 
I know how to do a N Epsilon proof but don't you have to have |s_n + t_n - (s + t)| < epsilon??

And that is to show that the lim (s_n + t_n) = s + t. I need to know lim |s_n - t_n| = 0. i guess i am unsure how the abs effect the proof.
 
I have merged the two threads.
 

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