x^2+9y^2+4z^2-6xy-12yz+4xz=?
如果3y=x+2y,那么x *x+9*y*y+4*z*z-6xy-12yz+4xz的值是多少?
(2X+Z-Y)/(X^2-XY+XZ-YZ)-(Y-Z)/(X^2-XY-XZ+YZ)
x^2+y^2+xy=25/4,x^2+z^2+xz=169/4,y^2+z^2+yz=36,求xy+xz+yz
若x/2=1/y=z/3,且xy+xz+yz=99,求4x^2-2xz+3yz-9y^2的值.
若x/3=y=z/4,且xy+xz+yz=76,求2x*x+12y*y+9z*z的值
如果3y=x+2z,那么x^2+9y^2+4z^2-6xy-12yz+4xz=
设x,y,z∈R+,xy+yz+xz=1,证明不等式:(xy)^2/z+(xz)^2/y+(yz)^2/x+6xyz≥x
若X/3=Y/1=Z/4,且XY+XZ+YZ=76,求2X^2+12Y^2+9Z^2的值
若x/3=y/1=z/4,且xy+xz+yz=76,求2x²+12y²+9z²的值
若X/3=y/4=z/5,且xy+yz+xz=94,求代数式2X²+12y²+9z² 的值
已知x^3+y^3-z^3=96,xyz=4,x^2+y^2+z^2-xy+xz+yz=12,则x+y-z等于
解方程组xy+xz=8-x^2,yx+yz=12-y^2,zy+zx=-4-z^2