若3(X^2+Y^2+Z^2)=(X+Y+Z)^2,那么你知道X,Y,Z,之间有什么关系吗?

若x+y+z=3y=2z,则x/x+y+z=? 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 证明 ：x/(y+z)+y/(z+x)+z/(x+y)>=3/2其中 x,y,z>0 x+2y=3x+2z=4y+z 求x:y:z x/2=y/3=z/5 x+3y-z/x-3y+z 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-z)= x+y/2=z+x/3=y+z/4 x+y+z=27 若X:Y:Z=5:6:7那么(Y-X):(Y+Z)和(X+2Y+3Z):(3X+2Y+Z) 用行列式的性质证明：y+z z+x x+y x y z x+y y+z z+x =2 z x y z+x x+y y+z y z x 这个怎么证? 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-x)= 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知实数x y z满足x/(x+1)=y/(y+2)=z/(z+3)=(x+y+z)/3,求x+y+z的值 已知x,y,z 大于0,x+y+z=2,求证 xz/y(y+z)+zy/x(x+y)+yx/z(z+x)大于等于2/3 已知x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 若xyz=1,求证 x^2/(y+z)+y^2/(z+x)+z^2/(x+y)≥3/2 若x:y:z=3:2:1,则x+2y-z/2x-y+z=