设x>=0,y>=0,2x+y=6,求Z=(4x^2)+3xy+(y^2)-6x-3y的最值
设X+Y+Z=0求X^3+X^2Z-XYZ+Y^2Z+Y^3的值
已知4x-3y-6y=0,x+2y-7z=0.求x-y+z\x+y+z的值
若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值
若:X^2-4X+Y+6Y+√ Z-3+13=0求(xy)^z的值
已知3x-y+2z=x+2y+3z=0,求(3x^-xy+2y^)/(2x^+4xy+y^)值?
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,
已知实数x,y,z满足x²-6xy+10y²+4y+|z²-3z+2|+4=0,求(x+y
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知x、y、z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x^3+xy^2+x+x^2y+y^3+y=0,求5x-6y/3x+4y的值.
设变量xy满足约束条件x-y≥0,x+y-2≥0,3x-y-6≤0则目标函数z=2x-y
已知3x*+xy-2y*=0,求(x/y)-(y/x)-(x*+y*)/(xy)的值.*是平方