若x+y=5,xy=2,求x^2-xy+y^2 已知x+y=1,则代数式x^3+3xy+y^3的值是多少?

若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值 若xy=2（x+y),求 （3x-5xy+3y)÷(-x+3xy-y) 的值 若x-y=5,xy=6,求x^2-xy^2和x^2y+xy^2 已知x^2-xy=5,xy-y^2=-3求3(x^2-xy)-xy+y^2 若x+y=5,xy=6,求x^2y+xy^2的值 若1/x-1/y=2,求3x-2xy-3y/x-xy-y的值3x-2xy-3y/x-xy-y 不好意思，是3x-2xy-3y/x-2xy-y 已知xy^2=-2,求-xy（x^2y^5-xy^3-y)的值. 已知xy^2=-2 求-xy(x^2y^5-xy^3-y) xy^2=-3,求-xy(x^2y^5-xy^3-y) 若x^2+xy+y=14,y^2+xy+x=28,求x+y 若(y-x)/xy=3,求分式(2x+3xy-2y)/(x-2xy-y)的值 若y-x/xy=3,求分式2x+3xy-2y/x-2xy-y 已知X-XY-2Y=0求2X+3XY-Y/X-2XY+5Y 诺x+y=6,xy=4 求(5x-4y-3xy)-(8x-y+2xy) 已知xy/x+y=3,求代数式2x-5xy+2y/x-3xy+y 已知xy/x+y=2,求代数式3x-5xy+3y/-x+2xy-y的值 已知xy=2(x+y),求(5x-xy+5y)/(3xy-x-y)的值 已知xy=2(x+y),求5x-xy+5y/3xy-x-y的值