2x^2+4xy+2y^2-8z^2

化简(y-x)(z-x)/(x-2y+z)(x+y-2z)+（z-y)(x-y)/(xy-2z)(y+z-2x)+(x- (2X+Z-Y)/(X^2-XY+XZ-YZ)-(Y-Z)/(X^2-XY-XZ+YZ) 若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值 5yz/(y+z)=6,4xy/(z+x)=3,3xy/x+y=2 如果实数x,y,z满足x^2+y^2+z^2-(xy+yz+zx)=8,用A表示|x-y|,|y-z|,|z-x|中的最 1.已知3x-4y-z=0,2x+y-8z=0.求x²+y²+z²/xy+yz+2xz 的 初一 下 数学 1、已知3x-4y-z=0,2x+y-8z=0,求 x²+y²-z²÷xy 已知3x-4y-z=0,2x+y-8z=0,求xy+yz分之x二次方+y二次方-z二次方 已知3x-4y-z=0 2x+y-8z =0,求(x²+y²-z²)/(xy+yz)的值 已知三个数x,y,z,满足xy/x+y=-2，yz/y+z=4/3,zx/z+x=-4/3,求(xyz)/(xy+yz+ 初一数学已知3x-4y-z=0,2x+y-8z=0,且x,y,z不全为0求x²+2xy+z²/xy+ 已知3x－y+2z=x+2y+3z=0,求（3x^－xy+2y^)/(2x^+4xy+y^)值?