find the derivative of f(x)= (4x^2+4y^2)^2−4x^2y =16128 at point (4,4), regarding y as the independent variable and x as as the dependent variable

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anonymous · Answer

I got -1/2 as my answer but the software says am wrong

anonymous · Answer

my calculus is sort of rusty, and i'm doing it all by hand, soo...  i power ruled the f(x) implicitly in terms of d/dy and ended up with an ugly fraction <shruggs> not sure if Im heloing  but here it is..$$\frac{-(64xy + 64y^3)}{ (64x^3 + 128y^2 - 4x^2) }$$