Difficult Multivariate limit problem

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SUMMARY

The limit lim (x,y)→(0,0) of yln(x^2 + y^2) does not exist. The discussion focuses on evaluating the limit using polar coordinates, where the expression transforms to r sin(θ) ln(r^2) = (2 r ln(r))sin(θ). The key conclusion is that this limit approaches 0 if and only if lim_{r→0} r ln(r) = 0, which is established as true. The application of L'Hôpital's rule is deemed inappropriate due to the nature of the indeterminate forms encountered when approaching the limit along different paths.

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Homework Statement



I am supposed to show whether the limit:

lim (x,y)----> (0,0) of yln(x^2 + y^2) exists or doesn't.

Homework Equations





The Attempt at a Solution




I've tried numerous paths, but what it seems to come down to is showing that the y factor goes to zero quicker than the ln(x^2 +y^2) factor. And I don't believe l'hospital's rule is applicable.
 
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L'hospitals rule is applicable since you end of with inderterminate forms when you approach x and y separately.
 
In polar coordinates, [itex]y ln(x^2+ y^2)[/itex] becomes [itex]r sin(\theta) ln(r^2)= (2 r ln(r))sin(\theta)[/itex]. That will go to 0 independently of y if and only if [itex]\lim_{r\to 0} r ln(r)= 0[/itex]. Is that true?
 

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