Trying to press on through Epsilon-Delta proofs of limits (for more than one variable) and yet there's only one example I've found thus far of even a multi-variable Epsilon-Delta proof.(adsbygoogle = window.adsbygoogle || []).push({});

Would it be possible for someone to solve the Epsilon-Delta proof of the limit:

(xy^2)/(x^2+y^2). Note: The limit does *not* exist... along straight-line paths the limit is 0, yet on the x=y^2 parabola the limit is 1/2.

x=y^2

IE: (y^2)y^2/(y^2)^2+y^4 = y^4/2y^4 = 1/2.

Profs always say Epsilon-Delta proofs are among the hardest things to get in math... go figure! You try and get examples and its always the same 3 recycled over and over, and all are examples of limits which exist. Most are even polynomial aswell, which makes it super-easy. (Except you never see Polynomial proofs on exams, no they must give you rationals)

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# Epsilon-Delta Proofs of Limits

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