Use implicit differentiation where LaTeX:  \displaystyle y is a function of LaTeX:  \displaystyle x to find the derivative of LaTeX:  \displaystyle - 6 \log{\left(y \right)} \cos{\left(x \right)} + 8 \sin{\left(x^{2} \right)} \sin{\left(y^{2} \right)}=47

Taking the derivative of both sides using implicit differentiation gives: LaTeX:   16 x \sin{\left(y^{2} \right)} \cos{\left(x^{2} \right)} + 16 y y' \sin{\left(x^{2} \right)} \cos{\left(y^{2} \right)} + 6 \log{\left(y \right)} \sin{\left(x \right)} - \frac{6 y' \cos{\left(x \right)}}{y} = 0  Solving for LaTeX:  \displaystyle y' gives LaTeX:  \displaystyle y' = \frac{y \left(8 x \sin{\left(y^{2} \right)} \cos{\left(x^{2} \right)} + 3 \log{\left(y \right)} \sin{\left(x \right)}\right)}{- 8 y^{2} \sin{\left(x^{2} \right)} \cos{\left(y^{2} \right)} + 3 \cos{\left(x \right)}}