若1/x+1/y=2,则 x/(3x+3y)+(y+2xy)/(3x+3y)=

若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( ) 若1/x+1/y=2,则(2x-xy+2y)÷(3x+5xy+3y) 1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y) 已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y= 若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 若x^2-3x=1,则x^2y-3xy-y 1/x-1/y=3,求2x+3xy-2y/x-y 已知x/1-y/1=3,则5x+xy-5y/x+2y-y的值为 若实数x,y满足1/x-1/y=5,则分式3x-2xy-3y/x+xy-y的值等于? 一.x-y=2,则x²-2xy+y²= 二.x-y=-1,xy=3,则x³y-2x x+y)(x-y)+(x-y)^2-(6x^2y-2xy^2)/2y,其中x=-2,y=1/3 若1/x-1/y=1/3,求(2x+3xy-2y)/(x-3xy-y)