x²y-y²z+z²x-x²z+y²x+z²y-2xyz
1、x³+x²y-x²z-xyz
x³+y³+z³-3xyz为什么等于(x+y+z)(x²+y²+z
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
已知x,y,z为正整数,且满足x³-y³-z³=3xyz,x²=2(y+z),求
已知有理数x,y,z满足(x-z-2)²+(3x-6y-7)+|3y+3z-4|=0,则xyz=
已知x-2y+z=0,3x+6y-z=0(xyz≠0),求2x²+y²/x²+y²
(x-3y+2z)²=
已知x²+y²+z²-2x+4y-6z+14=0,求x+y-z/x+y+z的值
已知x,y,z满足x+y+2z=1,x²+y²+6z+1.5=0,求x,y,z的值
数学题已知xyz≠0,且x+y+z=1,x²+y²+z²=1,求1/x+1/y+1/z的值
分解因式:4x²-4xyz+y²z²-4z²
正整数x、y、z满足x&3-y&3-z&3=3xyz,x²=0(y+z),则xy+yz+xz=()