Use implicit differentiation where LaTeX: \displaystyle y is a function of LaTeX: \displaystyle x to find the derivative of LaTeX: \displaystyle 3 e^{x} \sin{\left(y^{2} \right)} - 9 \log{\left(y \right)} \cos{\left(x^{3} \right)}=25

Taking the derivative of both sides using implicit differentiation gives: LaTeX: 27 x^{2} \log{\left(y \right)} \sin{\left(x^{3} \right)} + 6 y y' e^{x} \cos{\left(y^{2} \right)} + 3 e^{x} \sin{\left(y^{2} \right)} - \frac{9 y' \cos{\left(x^{3} \right)}}{y} = 0 Solving for LaTeX: \displaystyle y' gives LaTeX: \displaystyle y' = \frac{y \left(9 x^{2} \log{\left(y \right)} \sin{\left(x^{3} \right)} + e^{x} \sin{\left(y^{2} \right)}\right)}{- 2 y^{2} e^{x} \cos{\left(y^{2} \right)} + 3 \cos{\left(x^{3} \right)}}