# Thread: implicit differentiation (I think)

1. ## implicit differentiation (I think)

Find an equation of the line tangent to the curve with equation $x^2 + xy + y^3 = 1$, at the
point (-1; 1)

im I right in thinking this is an implicit differentiation problem? I would implicitly find the derivative of the equation and then use point slope formula to wite the equation of the line correct?

how do I differentiate the above equation?

2. ## Re: implicit differentiation (I think)

Originally Posted by kingsolomonsgrave
Find an equation of the line tangent to the curve with equation $x^2 + xy + y^3 = 1$, at the point (-1; 1)

Yes indeed; $2x+y+xy'+3y^2y'=0$. Solve for $y'~.$