Can anyone show me how to find $\displaystyle \frac{dy}{dx}$ for $\displaystyle (x^2+y^2-1)(y-x^2-1) = 0$ at the points (0,1) and (0,0).

I know that I need to use the process of implicit differentiation but I don't know exactly how to apply it here. Do I need to expand the brackets first and then differentiate everything?