x-z=4,2y-z=1,x+y+z=-1求xyz的值

x+y+z=1 求xyz/(x+y)(y+z)(z+x)的最大值 已知实数xyz满足x/y+z+y/z+x+z/x+y=1求x^2/y+z+y^2/z+x+z^2/x+y的值 x*x+y*y+2z*z-2x+4y+4z+7=0,求xyz的值 已知XYz满足|X-Y|/4+z^2-z+1/4+根号2y+z=0,求(y+z)的值. 若xyz不等于0,且满足(y+z)/x=(x+z)/y=(x+y)/z,求（y+z)（x+z)（x+y)/xyz的值 若xyz不等于0,且(y+z)/x=(z+x)/y=(x+y)/z,求(y+z)(z+x)(x+y)/xyz的值? 若实数x,y,z满足条件√x+√y-1+√z-2=1/4(x+y+z+9),求xyz的值 已知实数xyz满足|x-2y|+2√(2y+z)+z-2z+1=0,求x+y+z的值 若x+y+z=0且xyz不等于0,求x(1/y+1/z)+y(1/x+1/z)+z(1/x+1/y)的值 已知4x-3y+z=0,x+2y-8z=0,xyz不等于0,求x+y-z/x-y+2z的值 有实数x,y,z；已知x+y+z=2,xyz=4；求Z的取值区间 设X+Y+Z=0求X^3+X^2Z-XYZ+Y^2Z+Y^3的值