已知x^+y^+z^-xy-zy-xz=0 求证x=y=z
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方+y方+z方-xy-yz-xz=0,求证x=y=z
1.已知:x^2+y^2+z^2=xy+yz+xz 求证:x=y=z
已知:x^2+y^2+z^2=xy+yz+xz 求证:x=y=z
已知:xyz=1,x+y+z=2,x^2+y^2+z^2=16求1/(xy+2z)+1/(zy+2x)+1/(xz+2y
解方程组xy+xz=8-x^2,yx+yz=12-y^2,zy+zx=-4-z^2
已知X+Y+Z=a,XY+YZ+XZ=b,求X*X+Y*Y+Z*Z的值
已知:xy/(x+y)=a,xz/(x+z)=b,yz/(y+z)=c,且abc不等于0,求证:x=2abc/(bc+a
已知:xy/(x+y)=a,xz/(x+z)=b,yz/(y+z)=c,且abc不等于0,求证:x=2abc/(bc+a
若x/3=y/1=z/4,且xy+xz+zy=76,求2x(2)+12y(2)+9z(2)
解方程组2X+YX^2=Y 2Y+ZY^2=Z 2Z+XZ^2=X
已知x+y+z=1,xy+yz+xz=0,求x^2+y^2+z^2的值.