x=2z²/(1+z²),y =2x²/(1+x²),z =2y²/(
已知x,y,z满足x+y+2z=1,x²+y²+6z+1.5=0,求x,y,z的值
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
若3x-2y-z=0,x+4y-3z=0,求3x²+y²/4x²-y²+z
(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=2,y-z=2,x+z=14,求x²-z²的值
已知x-y=2,y-z=2,x+z=14,求x²-z²的值.
已知x+y+z=0,求(y²+z²-x²)分之1+(z²+x²-y
初一 下 数学 1、已知3x-4y-z=0,2x+y-8z=0,求 x²+y²-z²÷xy
已知丨x+1丨+(y+2)²+丨z-1丨=0,求(x+y)²-(y+z)²-(z+x)
已知实数x、y、z满足:2x+3y+z=1,则x²+y²+z²的最小值为
代数式的恒等变形(1).已知x²+y²+z²-2x+4y-6z+14=0,求(x-y-z)