Consider the functions z= - e* In y, x= In (u cos v), and y = u sin v. z dz (a) Express au and as functions of u and v both by using the Chain Rule and by expressing z directly in terms of L dv and v before differentiating. dz (b) Evaluate and at (u,v) = av dz dz (a) Find each partial derivative needed to use the Chain Rule to find du 11 dz du 11 LM)=(2,3). ax du dy au 4