己知x=2,y+z=1,求代数式x2(-y-z)+4x(z+y)的值.
已知x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求代数式x2/(y+z)+y2/(x+z)+z2/
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
己知x,y,z都是非零有理数,且满足|x|/x+|y|/y+z/|z|=1,请你求xyz/|xyz|的值.求因为所以?
已知实数x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求x2/(y+z)+y2/(z+x)+z2/(
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
已知3/x=4/y=6/z,求代数式4y/3x+2y+z的值
x y z x+y--- = --- = ---- ----y+Z z+x x+y ,求 z 的值 .求 x+y----
已知X、Y、Z满足2X-Y+4Z=8(1);X-2Y-Z=7(2)求X-Y-Z的值
1 已知想x,y,z满足2x-y+4z=8,x-2y-z=7,求x-y+z的值
已知x+y-1的绝对值+x+2y+z的和的平方+x-3z的绝对值=0,求代数式x-y+z的值.
已知:(x+y-z)/z=(x-y+z)/y+(y+z-x)/x,且xyz≠0,求代数式[(x+y)(y+z)(x+z)
1.已知x,y,z满足2│x-y│+(根号2y-z)+z平方-z+(1/4)=0,求x,y,z值.