Use implicit differentiation where LaTeX:  \displaystyle y is a function of LaTeX:  \displaystyle x to find the derivative of LaTeX:  \displaystyle - x^{2} \log{\left(y \right)} + 3 \sqrt{2} \sqrt{y} e^{x}=47

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