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How can we prove that $\left|\frac{x^2y^3}{x^4+y^4}\right|\leq |x|+|y|$?

I got this as homework but don't even know where to start. I've tried developing $(x+y)^4$ but that didn't help to find a connection.

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If $x=0$ or $y=0$, then we got $0\leq 0$ else $|\frac{x^2y^3}{x^4+y^4}|\leq |\frac{x^2y^3}{2x^2y^2}|\leq \frac{1}{2}|y|\leq |x|+|y|$

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    I actually have that solution separately. What I need to prove is that exact inequality somehow.2012-12-04
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    I don't see what you are looking for, this is a proof,isn't it ? (I'm sorry I'm french and my english is ugly :()2012-12-04
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    It is a proof indeed. The professor gave us this alternative answer,involving $\frac{1}{2}y$, which he proved, and asked us to proof the other one as homework.2012-12-04
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    What "other one," @GrozavAlexIoan? You have one problem here.2012-12-04
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    BTW, you need to handle specially the (obvious) cases of $x=0$ or $y=0$.2012-12-04
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    @Thomas Andrew : Absolutely, thanks. ( I'm new on this kind of forum but is it recommended to edit my answer ?)2012-12-04
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    @matovitch Definitely change your answer. The goal is for the best answer, not the first answer. :)2012-12-04
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    I meant the other way. With |x|+|y|. Anyway I worked something out. Thank you for your help!2012-12-04