怎么计算:1.(x-2y+z)(-x+2y+z) 2.(2x-3y-1)(2x+3y-1)
1.(x+y-z)+(x-y+z)-(x-y-z) 2.2x-(3x-2y+3)-(5y-2)
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
计算:1.(-x+2y+3z)(x-2y-3z) 2.[(x/2+3y)^2-(y/2+x)^2+(3x-2/y)^2-
计算:3x-2y- [-4x+(z+3y)]
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
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
(y-x)/(x+z-2y)(x+y-2z)+(z-y)(x-y)/(x+y-2z)(y+z-2x)+(x-z)(y-z
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=
解三元一次方程组 1.{2x-y+z=1,3x+y-2z=2,x+2y-z=3 2.{3x-y+z=4,2x+3y-z=
x,y,z正整数 x>y>z证明 x^2x +y^2y+z^2z>x^(y+z)*y^(x+z)*z^(x+y)
x/2=y/3=z/5 x+3y-z/x-3y+z
如果,根号x-3+| y-2 |+z^2=2z-1 求 (x+z)^y