求偏导数
z=f(u) u=e^(kxy)/x^k 求z对x的偏导数
u对x的偏导=kye^(kxy)x^(-k)-ke^(kxy)x^(-k-1) =[k(xy-1)e^(kxy)]/[x^(k+1)] z对x的偏导=f'(u)*u'(x)=f'(u)*[k(xy-1)e^(kxy)]/[x^(k+1)]
答:Zx=f(x,y,y)(1+2*dy/dx);Zy=f(x,y,y)*(dx/dy+2) Zxx=f(x,y,y)(1+2*dy/dx)^2+f(x,y,y)*...详情>>
答:I came.详情>>