(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known dataI need to evaluate this limit by converting to polar coordinates:

lim (x,y) -> (0,0) of (x^2 + xy + y^2) / x^2 + y^2

2. Relevant equationsx = rcos(theta), y = rsin(theta)

3. The attempt at a solutionSo switching to polar I get:

[(rcos(theta))^2 + rcos(theta)rsin(theta) + (rsin(theta))^2] / (rcos(theta))^2 + (rsin(theta))^2

By pulling out the r^2 from the the top of the equation and the bottom of the equation, they can cancel. Then the denominator is cos(theta)^2 + sin(theta)^2 which equals 1.

So we get the limit of cos(theta)^2 + cos(theta)sin(theta) + sin(theta)^2 but I dont know what to do from here because this is the limit as r goes to 0 and there is no r?

I'm kinda stuck here...what can I do? We didn't really get taught this so I could be missing something simple.

Thanks!

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# Homework Help: Limit of polar coordinates

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