x:y:z=1:2:7 2x-y+3z=21
1.x+y+z=21,x-y=1,2x+z-y=13.2.3x+2y+z=13,x+y+2z=7 ,2z+3y-z=12
{x+y+z=1;x+3y+7z=-1;z+5y+8z=-2
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
x+2y-z=1 3x-3y+z=2 3x+3y+z=7
x-y-z=-1 3x+5y+7z=11 4x-y+2z=-1 分别求出x=?y=?z=?
{5x-3y+z=2{5x+2y-4z=3{-5x+y-z=2 {x-y-z=-1{3x+5y+7z{4x-y+2x=-
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,根号x-3+| y-2 |+z^2=2z-1 求 (x+z)^y
x+2y=3 x+y+z=36 2x+y+z=15 2y=3z x-y=1 x+2y+z x-z=-1 2x+z-y=1
x/2=y/3=z/5 x+3y-z/x-3y+z
若x-2y+4z=1,x+3y-7z=0,则y:z=?
已知x:y:z=4:5:7,求:(1)2x+3y+z/5z; (2)x+y/y+z.