f(x,y) = (2xy)/(x2 + y2), 0 if (x,y) = (0,0)(adsbygoogle = window.adsbygoogle || []).push({});

Now I'm supposed to evaluate this at (0,0). I take the first partial derivative and I get 0/0 but when I use the definition of derivatives I get a whole number. Why the hell is this?

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# Concerning partial derivatives

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