Calculus: implicit differentiation
posted by Anonymous .
Find dy/dx by implicit differentiation
1. x^3 xy+ y^2= 7
The given answer is (y3x^2)/ (2yx), but I'm not getting it.
2. How would I do this one? If I couldn't do the above one, which looks a heck of a lot simpler, I doubt I'll get through this one.
x^ (6/7) + y^ (8/5) = 16

x^3 xy+ y^2= 7
3x^2xdy/dxy+2ydy/dx=0
dy/dx(2yx)=y3x^2
Why is it you cannot get the answer?
x^ (6/7) + y^ (8/5) = 16
6/7 x^(2/7) + 8/5 y^(3/5)y'=0
y'= (6/7 x^(2/7))/(8/5 y^)3/5))
do you agree? 
you may need to adjust for the fact that 6/7  1 = 1/7, not 2/7