对x求偏导则把y看成常数(xz)'=x'*z+x*z'=z+x*z'(lny-lnz)'=0-(1/z)*z'z+x*z'=-(1/z)*z'z'=z/(-x-1/z)=-z²(xz+1)所以∂z/∂x=-z²(xz+1)对y求偏导则把x看成常数(xz)'=xz'(lny-lnz)'=1/y-(1/z)*z'x...