SOLUTION: Calculus Question Use implicit differentiation to find y' for x^3 + y^3 = 12xy

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Question 1142764: Calculus Question
Use implicit differentiation to find y' for x^3 + y^3 = 12xy

Answer by ikleyn(52800) About Me  (Show Source):
You can put this solution on YOUR website!
.
x%5E3+%2B+y%5E3 = 12xy


Differentiate, considering y as a function of x, y = y(x) :


    3x^2 + 3y^2*y' = 12y + 12x*y'


Collect the terms with y' in one side;  the terms with no y' in the other side :


     3y^2*y' - 12x*y' = 12y - 3x^2


     y'*(3y^2 - 12x) = 12y+-+3x%5E2.


Express  y' :


     y' = %2812y+-+3x%5E2%29%2F%283y%5E2-12x%29,   


or,  canceling the common factor 3 in the numerator and in the denominator,


     y' = %284y+-+x%5E2%29%2F%28y%5E2-4x%29,   


It is your answer.