Proving Series Convergence: \sum_{n=1}^{\infty}\frac{\sqrt{n+1}-\sqrt{n}}{n}

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analysis001
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Homework Statement


Prove that the series [itex]\sum_{n=1}^{\infty}\frac{\sqrt{n+1}-\sqrt{n}}{n}[/itex] converges.


The Attempt at a Solution


I think I'm going to use the comparison test but I'm having trouble coming up with a series to compare it to. Any clues would be great. Thanks!
 
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analysis001 said:

Homework Statement


Prove that the series [itex]\sum_{n=1}^{\infty}\frac{\sqrt{n+1}-\sqrt{n}}{n}[/itex] converges.

The Attempt at a Solution


I think I'm going to use the comparison test but I'm having trouble coming up with a series to compare it to. Any clues would be great. Thanks!
Try rationalizing the numerator.
 
SammyS said:
Try rationalizing the numerator.

Yeah, I've gotten to that point, so as of now I have: [itex]\sum_{n=1}^{\infty}\frac{1}{n(\sqrt{n+1}+\sqrt{n})}[/itex] but I'm still not sure what to compare it to.
 
analysis001 said:
Yeah, I've gotten to that point, so as of now I have: [itex]\sum_{n=1}^{\infty}\frac{1}{n(\sqrt{n+1}+\sqrt{n})}[/itex] but I'm still not sure what to compare it to.
Let's see ...

## \sqrt{n+1}\ \ > \sqrt{n} ##

How can that help ?
 
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