函数z=sin(xy)的全微分是-搜答案-拍题作业网

我来试试吧...z=e^xy*cos(x+y)Z'x=ye^xycos(x+y)-e^xysin(x+y)Z'y=xe^xycos(x+y)-e^xysin(x+y)故dZ=[ye^xycos(x+y

设u=xy,v=lnx+g(xy),则x(∂z/∂x)-y(∂z/∂y)=∂f/∂v.原因如下：dz=(∂f/

e^(-xy)-2z+e^z=0-ye^(-xy)-2z'(x)+e^zz'(x)=0z'(x)=ye^(-xy)/(e^z-2)-xe^(-xy)-2z'(y)+e^zz'(y)=0z'(y)=xe

Z=e^xy在x处的导函数为ye^(xy)在y处的导函数为xe^(xy)dz=ye^(xy)dx+xe^(xy)dy=2e^2dx+e^2dy

对方程两边求全微分得：(e^z-1)dz+y^3dx+3xy^2dy=0（方法和求导类似）移项,有dz=-(y^3dx+3xy^2dy)/(e^z-1)

dz=[sin(xy)+xycosxy]dx+(x^2cosxy)dydz|(1,1)=(sin1+cos1)dx+cos1dy再问：先求dx，dy，详细过程谢谢再答：=sin(xy)+xycosxy

(y^2+2xy-cos(y+z))/(e^z+cos(y+z))再问：没有过程吗？再答：求导：e^z*dz-y^2-2xy+cos(y+z)(1+dz)=0把含有dz的项移到一起：(e^z+cos(

解；z(x)=2x+2y²z(y)=4xy+12y²dz=(2x+2y²)dx+(4xy+12y²)dy

...偏z/偏x=-8切线（x-8)/8=(y+8)/1=(z-8)/8,法平面：x+z-8=1(8):应该是抛物线y^8=8x吧抛物线在（8,8...函数z=In(x+y)沿着这抛物现在该点处偏向x

dz=2xdy+2ydx

两边即对数得：lnz=xy*ln(lnu),不妨记u=x^2+y^2z'x/z=yln(lnu)+2x^2y/lnu,z'x=z[yln(lnu)+2x^2y/lnu]z'y/z=xln(lnu)+2

dz=[yIn(xy)+y]dx+[xIn(xy)+x]dy分开求导

dz=Z'xdx+Z'ydy=2xcos(x^2+y^2)dx+2ycos(x^2+y^2)dy

再问：啊不好意思搞错了。。是z=e^(x^2+y^2)，求dz，谢谢你帮我解答一下吧。。再答：

dz=1/y/(1+x^2/y^2)*dx-x/y^2/(1+x^2/y^2)*dy

dz=2xydx+x^2dy再问：有全过程吗再答：en我想知道这里的X^2Y是指的X得平方乘以Y吗？如果是过程如下：dz/dx=2xydz/dy=x^2dz=2xydx+x^2dy再问：是X的2Y次方

dz=(y+1/y)dx+(x-x/y^2)dy

再问：就是这个吗？再答：是的。如还有不懂请追问，懂了请采纳。再问：还有这三题