已知x^2/(y^2+z^2+yz)+y^2/(x^2+z^2+zx)+z^2(y^2+x^2+yx)>=1
已知x^2/(y^2+z^2+yz)+y^2/(x^2+z^2+zx)+z^2(y^2+x^2+yx)>=1
(x^2+yz)/(x^2+x(y-z)-yz)+(y^2-xz)/(y^2+y(x+z)+zx)+(z^2+yx)/(
已知xy:yz:zx=3:2:1,求①x:y:z ②x/yz:y/zx
已知xy/x+y=3,yz/y+z=2,zx/z+x=1,求y的值
化简x^2-yz/[x^2-(y+z)x+yz]+y^2-zx/[y^2-(z+x)y+zx]+z^2-xy/[z^2-
已知x+y+z=1,x²+y²+z²=2求xy+yz+zx
已知x-y=5,z-y=10,X^2+Y^2+Z^2-XY-YZ-ZX
已知三个数x,y,z,满足xy/x+y=-2,yz/y+z=4/3,zx/z+x=-4/3,求(xyz)/(xy+yz+
已知xy/x+1=1 yz/y+z=2 zx/z+x=3 求x
证明 (x+y+z)^2>3(xy+yz+zx)
一道数学题,已知x+y+z=1,x^2+y^2+z^2=2,问xy+yz+zx,x^3+y^3+z^3
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