1/x-1/y=3 2X+3XY-2Y/X-2XY-Y=

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 1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y) x-y/x+y=-1/2,x*x-xy-2y*y/x*x-3xy+2y*y的解是多少?同上,请将过程写出, （x+2y-3xy)-(-2x-y+xy),其中x+y=1/2,xy=-1/2 已知3/(x-y)=1/xy 求(-x-2xy+y)/ (2x+3xy-2y) 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 x-y=1,xy=2.求：(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 .已知:x-y=1,xy=-2.求:(-2xy+2 x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 若x-y=4,xy=1,则(2x+y-2xy)-(3x+2y+xy)-(4xy+3y-5x)= (-2xy+2x+5y)-(3xy+2y-2x)-(x+4y+xy)其中x-y=4xy=-1 化简求值x-4y/2x-7xy+3y×x-2xy-3y/2x+3xy-2y÷3x-6y/4x-4xy+y,其中：x=1999,y=-1 因式分解x^2y^2+x^2y+xy^2+3xy+x+y+1 已知x-y=3,xy=1,求（-2x+2x+3y)-(3xy+2y-2x)-(x+4y+xy) 已知x(x-1)-(x²-y)=-3,求(x²y+xy²)÷xy-2y 当x=2 y=2分之1 时,代数式(x+y)(x-y)+(x-y)^-(x^-3xy ) ( )-(x^2+3xy)=-xy-1/3y^2 1/x-1/y=3,求2x+3xy-2y/x-y