Starting with y^2-xy=2, then y'=y/(2y-x)(adsbygoogle = window.adsbygoogle || []).push({});

y''=(2y-x)y'-y(2y'-1)/(2y-x)^2

substitute y' in:

y''=(2y-x)(y/2y-x) - y(2(y/2y-x)-1)

the (2y-x) cancels:

y''=(y) - y(2y/2y-x)-1)

distribute:

y'' = y - (2y^2)/(2y-x)-y

Somewhere I need y^2-xy so I can replace it with the original 2, but I'm not getting it.

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# Second Derivative Doesn't Work!

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