Use implicit differentiation where LaTeX:  \displaystyle y is a function of LaTeX:  \displaystyle x to find the derivative of LaTeX:  \displaystyle - 8 e^{x} \log{\left(y \right)} + 3 \sin{\left(y^{3} \right)} \cos{\left(x^{2} \right)}=-3

Taking the derivative of both sides using implicit differentiation gives: LaTeX:   - 6 x \sin{\left(x^{2} \right)} \sin{\left(y^{3} \right)} + 9 y^{2} y' \cos{\left(x^{2} \right)} \cos{\left(y^{3} \right)} - 8 e^{x} \log{\left(y \right)} - \frac{8 y' e^{x}}{y} = 0  Solving for LaTeX:  \displaystyle y' gives LaTeX:  \displaystyle y' = \frac{2 y \left(3 x \sin{\left(x^{2} \right)} \sin{\left(y^{3} \right)} + 4 e^{x} \log{\left(y \right)}\right)}{9 y^{3} \cos{\left(x^{2} \right)} \cos{\left(y^{3} \right)} - 8 e^{x}}