<p>dy/dx if y= x^3+y^3=12xy. I keep doing this problem over and over again but the answer I get isn't a choice but VERY similar to one. I get (4-x^2)/(y^2-4x). Any help would be greatly appreciated!!! I don't want to look like an idiot pointing out a mistake to my professor if I'm wrong.</p>
<p>use wolfram alpha: <a href=“differentiate x^3+y^3=12xy - Wolfram|Alpha”>differentiate x^3+y^3=12xy - Wolfram|Alpha;
<p>x^3 + y^3 = 12xy
3x^2 + 3y^2dy/dx = 12(y + xdy/dx) [Differentiate w/ respect to x]
3x^2 + dy/dx (3y^2) = 12y + dy/dx(12x) [Simplify]
dy/dx(3y^2) - dy/dx(12x) = 12y - 3x^2 [Get all dy/dx on one side]
dy/dx(3y^2 - 12x) = 12y - 3x^2 [Factor out dy/dx]
dy/dx = 12y - 3x^2/3y^2 - 12x [Divide by (3y^2 - 12x)
dy/dx = 4y - x^2/y^2 - 4x [Factor out a 3]
dy/dx = x^2 - 4y/4x - y^2 [Multiple by a (-)…previous row is also an acceptable answer]</p>
<p>Thanks!!! 10char</p>