设z=|xy|,求dz

设z=|xy|,求dz 设z=(x+y)^xy,求dz 设z=(x+2y)e^xy,求dz 设Z=f(x^2 +y,2xy),求dz/dx和dz/dy z=xe^xy,求dz 急求“设函数z=xe^(-xy)+sin(xy),则dz=”这道题的做法, 设Z=e^xy COS(xy),求dz|(0,1) 设z=u^2cosv^2,u=x+y,v=xy,求dz/dx,dz/dy.高数题 设z=ln(eu+v),v=xy,u=x2-y2,求dz/dx,dz/dy. 设z=arctany/x,求dz? 设z=x^y,求dz 设Z=(1+xy)^x,求dz| x=1 y=1 设z=arctan(xy),y=e^x ,求dz/dx ． 二元函数 设z=(x平方-y平方)e的xy次方,求dz 设z=f(2x+3y,e^xy),求dz 设z=arctan(xy)+2x^2+y^2,求dz 设Z=x²+2xy,求dz正确打赏. 设z=f(xy,e^x+y),求dz高数计算题,坐等大侠