\begin{array}{l} \text { 10. } w=\ln \left(x^{2}+y^{2}+z^{2}\right), \quad x=u e^{v} \sin u, \quad y=u e^{v} \cos u \\ z=u e^{w} ; \quad(u, v)=(-2,0) \end{array} In Exercises 9 and 10, (a)

express ðw/ðu and ðw/ðv as functions of u and v both by using the Chain Rule and by expressing w directly in terms of u and v before differentiating. Then (b) evaluate ðw/ðu and ðw /ðv at the given point (u, v).