xy(x-y)+yz(y-z)+zx(z-x)因式分解

xy(x-y)+yz(y-z)+zx(z-x)因式分解 (1/x+1/y+1/z)×(xy)/(xy+yz+zx) 化简x^2-yz/[x^2-(y+z)x+yz]+y^2-zx/[y^2-(z+x)y+zx]+z^2-xy/[z^2-(x+y)z+xy] (x+y+z)(xy+yz+zx)等于多少 分解因式：xyz-yz-zx-xy+x+y+z-1 如果xyz+xy+yz+zx+x+y+z=1975,求自然数x,y,z过程~ xy(x-y)+yz(y-z)+zx(z-x)因式分解对称轮换式 分式题:xy=x+y,yz=2(y+z),zx=3(z+x),求xyz/(xy+yz+xz)xy=x+y,yz=2(y+z),zx=3(z+x),求xyz/(xy+yz+xz) 求证不等式 xyz[yz(y+z)+zx(z+x)+xy(x+y)]>=2(xy+yz+xz)^2 已知XY=2(X+Y),YZ=4(Y+Z),ZX=5(Z+X),求X,Y,Z已知XY=2(X+Y),YZ=4(Y+Z),ZX=5(Z+X),求X,Y,Z 方程组xy/x+y=2 yz/y+z=4 zx/x+z=5 求x,y,z 求证：(x^3/x+y)+(y^3/y+z)+(z^3/z+x)大于等于（xy+yz+zx)/2 已知x,y,z>0 求证:xy(x+y)+yz(y+z)+zx(z+x)>=6xyz xy+yz+zx=1,求x√yz+y√zx+z√xy是小于等于 已知yz+zx+xy=1,确定的z=z(x,y),求dz. xy 2yz 3zx 4xyz________ = ________ = _______ = ___________ (xyz不等于0)x+y+xy y+z+yz z+x+zx xy+yz+zx最好有解题思路 算出 X Y Z 分别等于几 (x^2+yz)/(x^2+x(y-z)-yz)+(y^2-xz)/(y^2+y(x+z)+zx)+(z^2+yx)/(x^2-z(x-y)-yx)最后一项应为：(z^2-xy)/(z^2+z(y-x)-xy) (x+y-xy)/(x+y+2xy)=(y+z-2yz)/(y+z+3yz)=(z+x-3zx)/(z+x+4zx),且2/x=3/y=1/z,则xyz=?