Another sequence convergence proof

antiemptyv
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Homework Statement



Let y_n := \sqrt{n+1} - \sqrt{n} for n \in \mathbb{N}. Show that (y_n) converges.

Homework Equations



The Attempt at a Solution



I see that it converges to 0. I just need a nudge in the right direction at getting into | \sqrt{n+1} - \sqrt{n} - 0 | = | \sqrt{n+1} - \sqrt{n} | to show it's less than any \epsilon > 0. Any manipulating I've tried so far makes the terms way too big to work with.
 
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How about

\left(\sqrt{n+1} - \sqrt{n}\right) \cdot \frac{\sqrt{n+1} + \sqrt{n}}{\sqrt{n+1} + \sqrt{n}}
 
ohhhh, i see it now.
 
What do you do after
1/(sqrt{n+1)+sqrt{n}) ??
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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