How do you differentiate 5xy + y^3 = 2x + 3y?

1 Answer
Aug 4, 2015

I found: (dy)/(dx)=(2-5y)/(5x+3y^2-3)

Explanation:

You can use implicit differentiation rememberig that y represents a function of x and needs to be differentiated accordingly;
for example: if you have y^2 you differentiate it to get:
2y*(dy)/(dx) where you use (dy)/(dx) to take into account the dependence with x.
In your case you get:
5y+5x(dy)/(dx)+3y^2(dy)/(dx)=2+3(dy)/(dx)
collect (dy)/(dx):
(dy)/(dx)(5x+3y^2-3)=2-5y
and:
(dy)/(dx)=(2-5y)/(5x+3y^2-3)