3x+2y+z=30,3x+y+2z=14,5x+3z=44,3x+2z=?
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
x/2=y/3=z/5 x+3y-z/x-3y+z
3x+2y+z=30,3x+y+2z=14,5x+3z=44,3x+2z=?
{x+y+z=1;x+3y+7z=-1;z+5y+8z=-2
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
3x+2y+z=14 ,x+y+z=10,z+2x+3y=1 5
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
已知2x+5y+4z=15.7x+y+3z=14 则x+y+z=?
1.x+y+z=30,3x+y-z=50,x,y,z为非负数,求5x+4y+2z取值范围.
如果,根号x-3+| y-2 |+z^2=2z-1 求 (x+z)^y
3道高数题,1,函数F(x,y,z)=(e^x) * y * (z^2) ,其中z=z(x,y)是由x+y+z+xyz=
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,