已知:(x2:z+y)+(y2:x+z)+(z2:x+y)=0,求(x:z+y)+(y:x+z)+(z:x+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/
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/(
1.已知x2+y2+z2-2x+4y-6z+14=0,求x+y+z的值.
已知x2+4y2+z2-2x+4y-6z+11=0 求x+y+z的值
已知x+y+z=1,x2+y2+z2=2,x3+y3+z3=3,求xy(x+y)+yz(y+z)+zx(z+x)的值
已知x+y+z=1,xy+yz+zx=2,xyz2,求x2(y+z)+y2(z+x)+z2(x+y)的值
已知x、y、z满足方程组:x+y-z=6;y+z-x=2;z+x-y=0 求x、y、z的值
已知a>0,实数x,y,z满足x+y+z=a,x2+y2+z2=a2/2,求x的取值范围
已知x+y-z/z=x-y+z/y=-x+y+z/x,且xyz不等于0,求分式[(x+y)(x+z)(y+z)]/xyz
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)
已知xyz=1,x+y+z=2,x2+y2+z2=16,求1/x+y+1/y+z+1/x+z
x y z x+y--- = --- = ---- ----y+Z z+x x+y ,求 z 的值 .求 x+y----