What is the limit as (x,y) approaches (0,0) for the function x^2/(x+y)?

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SUMMARY

The limit of the function x^2/(x+y) as (x,y) approaches (0,0) does not exist. Attempts to evaluate the limit by substituting y with 0, mx, or x^2 consistently yield a limit of zero. However, by approaching along the path y = -x, the limit diverges to infinity. This demonstrates that the limit is path-dependent, confirming that it does not exist overall.

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Mingy Jongo
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Homework Statement



Find the limit as (x,y) approaches (0,0):

Homework Equations



x^2/(x+y)

The Attempt at a Solution



I have tried replacing y with 0, mx, x^2, etc. (and likewise with x), and all give me a limit of zero. So I tried to think of ways I could use the definition of a limit, squeeze theorem, L'Hopital's rule, etc. to prove it, but there does not appear to be a way. I'm starting to think that a limit might not even exist. Is there something elementary I'm overlooking?
 
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It is a lot easier to show the limit does not exist. All you have to do is find one path towards (0,0) that produces a limit that is not zero. Maybe you could try a quadratic, or a cubic..
 
I figured it out a while ago. If y=-x, the limit as x->0 is infinity, not zero.
 

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