Converge or diverge? (partial frac. long division)

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Homework Help Overview

The discussion revolves around determining the convergence or divergence of a sequence defined by An=7+4n^2/n+2n^2. Participants are exploring methods to find the limit of the sequence as n approaches infinity.

Discussion Character

  • Conceptual clarification, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the relevance of using integrals and partial fractions, with some suggesting dividing the numerator and denominator by n^2 as a potential approach. There is uncertainty about whether to apply integral or derivative concepts in this context.

Discussion Status

Multiple interpretations of the problem are being explored, with some participants providing guidance on focusing on limits rather than integrals. There is a clear emphasis on taking the limit of the sequence as n approaches infinity, although there is no consensus on the correct approach or outcome.

Contextual Notes

Participants are grappling with the requirement to find the limit if the sequence converges, while also questioning the necessity of using integrals or derivatives in this scenario.

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Determine whether the sequence converges or diverges. If it converges, find the limit.
An=7+4n^2/n+2n^2
I know you have to compare it to the integral of the same equation, so I do this and the only means of integration I believe to be is by partial fractions, since degree of top equals degree of bottom but I am stuck on the long division, haven't done it in so long can't remember how to. any tips would be great.
 
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Forget the integral test for sequences. That's for summing series. To find the limit think about dividing the numerator and denominator by n^2. Does that ring a bell?
 
the only thing is it says if it converges find the limit and i know it doesn't diverge so I need to find out the value do i still take the integral of it or what?
 
all you ever do with sequences to find the value they approach is take the limit of it as n -> inf of your general term.

when you find the limit of a sequence all you do is take the limit of it. That's it.
 
are you sure you don't take the integral or derivative? because if not there must be a trick to this one i find that the lim as n->inf. goes to 0 when plugging into the original given equation, but that isn't the right answer, any ideas?
 
I am REALLY sure that i) there is no use in taking the integral and ii) you don't need to take the derivative. The limit as n->inf does not go to 0. I already told you what to do. Divide the numerator and denominator by n^2 and then take a another look at it.
 

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