Use implicit differentiation where LaTeX:  \displaystyle y is a function of LaTeX:  \displaystyle x to find the derivative of LaTeX:  \displaystyle - 10 \sqrt{2} \sqrt{y} \sin{\left(x^{3} \right)} + 4 e^{y} \cos{\left(x \right)}=-2

Taking the derivative of both sides using implicit differentiation gives: LaTeX:   - 30 \sqrt{2} x^{2} \sqrt{y} \cos{\left(x^{3} \right)} + 4 y' e^{y} \cos{\left(x \right)} - 4 e^{y} \sin{\left(x \right)} - \frac{5 \sqrt{2} y' \sin{\left(x^{3} \right)}}{\sqrt{y}} = 0  Solving for LaTeX:  \displaystyle y' gives LaTeX:  \displaystyle y' = \frac{2 \left(15 \sqrt{2} x^{2} y \cos{\left(x^{3} \right)} + 2 \sqrt{y} e^{y} \sin{\left(x \right)}\right)}{4 \sqrt{y} e^{y} \cos{\left(x \right)} - 5 \sqrt{2} \sin{\left(x^{3} \right)}}