已知x^2+xy+y^2=7,x^2-xy+y^2的最大值为m,最小值为n,求m+n

已知X+y=6,xy=7 求x^2y+xy^2=已知X+y=6,xy=7 x^2y+xy^2 已知xy/x+y=3,则代数式2x-7xy+2y/-x+xy-y的值是多少? 已知x*x+xy-2y*y=7 求整数x y的值 已知x=3y,试求（x-y)^2+2xy-y^2/x^2+7xy+y^2 已知x=3y,试求(x-y)^2+2xy-y^2/x^2+7xy+y^2 已知xy^2=-2求xy（2x^3y^7+5x^2y 已知,x-y=2,xy=7 求x^2 y-xy^2 已知x+y=0,xy=-7,求x^2y+xy^2 已知x+y=2,xy=7求x²y+xy²的值 已知整数x和y,满足x^+xy-2y^=7,求xy的值 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=1,xy=-2,则x²y+xy²-2xy 已知:x/y=-2,求x^2-2xy-3y^2/x^-6xy 已知x-xy=8,xy-y=-9,求x+y-2xy的值 已知X/Y=2/7,求x^2-3XY+2Y^2/X^2-2XY+Y^2 已知x/y=7/2,求2x+3xy+2y/x+2xy+y的值 已知x.y满足X2-y2=2xy.则x-y/x+y=?x. 已知x-y=8 xy=7,则3xy-2x+2y+4(y-x)²=?