Question

设z = f(u,v),而u=x+y,v=xy,其中f具有一阶连续偏导数,则∂z/∂x

Answer 1

∂z/∂x=(∂f(u,v)/∂u)*(∂u/∂x)+(∂f(u,v)/∂v)*(∂v/∂x)=(∂f(u,v)/∂u+(∂f(u,v)/∂v)*y