xyz+2x+2y+1=250000 求：x,y,z的值

设X+Y+Z=0求X^3+X^2Z-XYZ+Y^2Z+Y^3的值 x*x+y*y+2z*z-2x+4y+4z+7=0,求xyz的值 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 已知xyz适合关系式√3x+y-z-2+√2x+y-z=√x+y-2011+2011-x-y,试求xyz的值 x+y+z=1 求xyz/(x+y)(y+z)(z+x)的最大值 2（根号x+根号(y-1)+根号（z-2))=x+y=z,求xyz的值 已知xyz不等于0,且x+2y-z=0,7x-y-z=0,求x+y+z/2x-y-z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 已知XYZ满足方程组 X+Y-Z=6 Y+Z-X=2 Z+X-y=0 求X Y Z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?