Question

Calculate dy/dx when xy^3 + y =3x

Answer 1

The answer is the option D.

You have to use implicit derivative

1) dy / dx = y'

2)

$xy^3+y=3x y^3+3xy^2y'+y'=3 (3xy^2+1)y'=3-y^3 y'= (3-y^3)/(3xy^2+1) y'=(3-y^3)/(1+3xy^2)$