已知XY+X/X+Y+1=2 XZ+2X/X+Z+2=3 (Y+1)(Z+2)/Y+Z+3=4 求X+Y+Z的值已知(XY+X)/(X+Y+1)=2 (XZ+2X)/(X+Z+2)=3 [(Y+1)(Z+2)]/(Y+Z+3)=4 求X+Y+Z的值

已知xy(x+y)^-1=1,yz(y+z)^-1=2,xz(z+x)^-1=3 求zyx(zy+xz+xy)^-1=? 已知xy(x+y)^-1=1,yz(y+z)^-1=2,xz(z+x)^-1=3,试求xyz(xy+yz+xz)^-1的值 已知xy(x+y)^-1=1,yz(y+z)^-1=2,xz(z+x)^-1=3,试求xyz(xy+yz+xz)^-1的值 已知1=xy/x+y,2=yz/y+z,3=xz/x+z,求 X的值 (2X+Z-Y)/(X^2-XY+XZ-YZ)-(Y-Z)/(X^2-XY-XZ+YZ) 已知x＜0＜z,xy＞0,且|y|＞|z|＞|x|,求y/|xy|+1/|x|-2xz/|xz|的值 已知x+y+z=2,xz+zy+xy=1,求x^2+y^2+z^2=? 已知x+y+z=1,xy+yz+xz=0,求x^2+y^2+z^2的值. 已知x+y+z=1,x²+y²+z²=2求xy+yz+xz的值 已知|x+2|+(y-1)=-|z|,求x²-2xy-5x²+12xz+3xy-z²-8xz-2x²的值|x+2|+（y-1)²=-|z| 设x,y,z∈R+,xy+yz+xz=1,证明不等式:(xy)^2/z+(xz)^2/y+(yz)^2/x+6xyz≥x+y+zRt 已知XY+X/X+Y+1=2 XZ+2X/X+Z+2=3 (Y+1)(Z+2)/Y+Z+3=4 求X+Y+Z的值已知(XY+X)/(X+Y+1)=2 (XZ+2X)/(X+Z+2)=3 [(Y+1)(Z+2)]/(Y+Z+3)=4 求X+Y+Z的值 已知x＜0＜z,xy＞0,且|y|＞|z|＞|x|,求y/|xy|+1/|x|-|x-y|的值...急....算式错了...应该是求y/|xy|+1/|x|-2xz/|xz|的值 化简(2x-y-z/x^2-xy-xz+yz)+(2y-x-z/y^2-xy-yz+xz)+(2x-x-y/z^2-xz-yz+xy) 已知(x-3)^2+(y+1)^2+z^2=0,求x^2-2xy-5x^2+12xz+3xy-z^2-8xz-2x^2的值 已知（x-3）²+｜y+1｜+z=0,求：x²－2xy－（5x²－12xz－3xy）－（z²＋8xz＋2x² 已知(x-3)²+|y+1|+z²=0求x²-2xy-5x²+12xz+3xy-z²-8xz-2x²的值 代数 x^-y^/ x^-(y-z)^ 除以 x^+2xy+y^/(x-y)^-z^ 乘 x^+xy-xz/x^-xy