d2y/dx2 = d/dy [1/2 (y'^2)](adsbygoogle = window.adsbygoogle || []).push({});

so how do we show that the LHS = RHS? starting from the LHS?

i don't really understand.

my lecturer made it become d2y/dx2 = dy/dx * d/dy * y' and he showed it equals RHS

i understand how he get to dy/dx * d/dy * y'

but shouldn't that become dy/dx *y' * d/dy which is (y')^2 * d/dy? so where did the 1/2 from the RHS come from?

any help? thanks!

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# Homework Help: D2y / dx2

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