Math  Implict differentiation
posted by Ren on .
How do I find the value of d^2y/dx^2 for the function defined implicitly by xy^2 + y = 2 at the point (1,2)?

xy^2+y=2
y^2 dx + 2xy dy+dy=0
dy/dx ( 2xy+1)=y^2
dy/dx= y^2(1/(2xy+1)
dy"/dx"= 2y/(2xy+1) y^2/(2xy+1)^2 * (2y*xdy/dx+2y)
Put for dy/dx y^2/(2xy+1)
then put number (1,2)
CHECK MY WORK, I have a headache (Elm pollen).