Consider the functions z = e" In y, x = In (u cos v), and y = u sin v. dz oz and - as functions of u and v both by using the Chain Rule and by expressing z directly in terms of u and v before differentiating. (a) Express du z dz (b) Evaluate and , at (u,v) = |7.3dz (a) Find each partial derivative needed to use the Chain Rule to find du dz In y JX du dz sin v du Express z directly in terms of u and v. dz Using either method, du =dz Using either method, du (Type an expression using u and v as the variables.) dz Find each partial derivative needed to use the Chain Rule to find dx =dz Using either method, (Type an expression using u and v as the variables.) dz (b) (Type an exact answer.) 7 3 dz (Type an exact answer.) 7