已知1-1/2(1/3-y)^2=2+|3-x|/2,求3x^2y-[2xy^2-2(xy-3/2x^2y)+xy]+3

已知3/(x-y)=1/xy 求(-x-2xy+y)/ (2x+3xy-2y) 已知：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 已知:xy+x=-1,xy-y=-2,求多项式-x-[2y-2(xy+x)的平方+3x]+2[x+(xy-y)的平方]的 已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y= 已知x-y=3,xy=1,求（-2x+2x+3y)-(3xy+2y-2x)-(x+4y+xy) x-y=1,xy=2.求：(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值 已知1/x+1/y=5 求2x-3xy+2y/3x+2xy+3y 已知1/x-1/y=2,求3x+7xy-3y/2x-3xy-2y 已知x-y=-1,xy=3,求x^3y-2x^2y^2+xy^3 已知1/x-1/y=3,求分式(2x+3xy-2y)/(x-2xy-y)