先化简后求值(xy-x^2)÷(x^2-2xy+y^2)/(xy)*(x-y)/(x^2) x=-2005 y=-2

先化简后求值(xy-x^2)÷(x^2-2xy+y^2)/(xy)*(x-y)/(x^2) x=-2005 y=-2 先化简再求值：(x-y/x)÷[x-(2xy-y^2/x)],其中x=2013 先化简在求值[2x(x^2y-xy^2)+xy(xy-x^2)]÷(x^2y),其中x=2008,y=2007 先化简,再求值:(xy-x^2)÷x^2-2xy+y^2/xy*x-y/x^2,其中x=2009,y=2010 先化简,再求值:x-y/x÷【x-(2xy-y2)/x】,其中x=2,y=-1 快速! 先化简再求值 [2x（x^2y-xy^2）+xy(xy-x^2)]÷x^2y 其中=x2008 y=2004 先化简再求值 [2x（x^2y-xy^2）+xy(xy-x^2)]÷x^2y 其中=x2008 y=2004用简便方法算 先化简,后求值:xy分之(x-y)÷(x-y)*y²-2xy+x²分之xy,其中x=3.y=-1 化简求值：[（xy-2)²+4xy-4]÷(xy),其中x=10,y=1/25 [6xy-3(xy-1/2x2y)]÷3xy,其中x=2008,y=2009先化简再求值 先化简,再求值：[-xy/(x-y)^2]^4*(x^2-xy/x)3*x^4/y^10÷(x/xy-y^2)^5先化简,再求值：[-(xy)/(x-y)^2]^4*(x^2-xy/x)3*x^4/y^10÷(x/xy-y^2)^5,其中x=-2,y=4. 化简求值:[4(xy-1)²-(xy+2)(2-xy)]÷ -1/4 xy,其中x=-2,y=1/5注意：是-1/4xy 先化简,再求值:(x^2-2xy+y^2)/(x^2-xy)÷(x/y-y/x),其中x=3-√3,y=√3 先化简再求值(x²+xy-2y²)/(x²-2xy+y²) 4X的2次方+3XY-X的二次方-3XY+9 先化简 ,求值 -3x平方-4xy-6xy-(-y平方)-2x平方-3y平方求值 先化简再求值,x三次方+xy-2xy÷xy+y分之y-x,其中x=2,y=-3 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