x+y+z=5,xx+yy+zz=6,求xy-xz-yz的解
x+y+z=5,xx+yy+zz=6,求xy-xz-yz的解
知x/3=y/4=z/5,求(xy+yz+xz)/xx+yy+zz
已知x-y=5,y-z=4,求xx+yy+zz-xy-yz-xz的值
已知X+Y+Z=1,且XY+YZ+XZ=0,求XX+YY+ZZ的值?
若x/3=y/4=z/5,则(xy+yz=xz)/(xx+yy+zz)的值为
已知X+4Y+3X=3X-2Y-5Z=0(XYZ不等于0),求XY+YZ+2XZ/2XX-3YY+7ZZ的值
已知x,y,z是三角形的三条边长,且xx+yy+zz=xy+yz+xz,是判断三角形形状
已知,x/3 = y/1 = z/2 ,求 2xx - 2yy + 5zz /xy + yz +zx 的值.(/表示分数
已知x=1/2 y=1/3 z=1/4 则(xx+yy-zz+2xy)/(xx-yy+zz-2xz) 得多少?
求方程组的正整数解:x√(yz)+y√(xz)=39-xy y√(xz)+z√(xy)=52-yz z√(xy)+x√(
x+y+z=5,xy+xz+yz=1 ,求Z的最小值和最大值
已知14(XX+YY+ZZ)=(X+2Y+3Z)^2,求X:Y:Z