Use implicit differentiation where LaTeX:  \displaystyle y is a function of LaTeX:  \displaystyle x to find the derivative of LaTeX:  \displaystyle 3 \sqrt{x} e^{y^{2}} + 3 y e^{x^{2}}=36

Taking the derivative of both sides using implicit differentiation gives: LaTeX:   6 \sqrt{x} y y' e^{y^{2}} + 6 x y e^{x^{2}} + 3 y' e^{x^{2}} + \frac{3 e^{y^{2}}}{2 \sqrt{x}} = 0  Solving for LaTeX:  \displaystyle y' gives LaTeX:  \displaystyle y' = - \frac{4 x^{\frac{3}{2}} y e^{x^{2}} + e^{y^{2}}}{2 \sqrt{x} e^{x^{2}} + 4 x y e^{y^{2}}}