先化再求：（1/x-y-1/x+y)÷2y/x的平方+2xy+y的平方,其中x=√3+√2,y=√3-√2

[(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² [(-2x-y)^2-(2x+y)(2x-y)]÷2y-1/2y (x-y/1-x+y/1)÷2y/y-x计算错了，是(1/x-y-1/x+y)÷2y/y-x 先化简,再求值:y(x-y)-x(x+y)/x²-y²÷x²+y²/x+y,其中x=2,y=-1 1-[(x-y)/(x+2y)]÷[(x+y)(x-y)/(x+2y)²] 1-[(x-y)/(x+2y)]÷[(x+y)(x-y)/(x+2y)²]= 1／2x－（x+y／2x -x-y）÷（x+y) 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 化简：[(2x-y)平方+（2x+y)(2x-y)-4x(x-y+1)]÷2x 1、y-x/x²-y²2、(x-y)(y-z)(z-x)/(z-y)(y-x)(x-z) (x+y)(x-y)+(x-y)^2-(6x^2×y÷2y-2xy^2÷2y)其中x=-3,y=1/3 先化简,再求值[(2x+y)^2-(2x+y)(2x-y)-y(5x+y)]÷(1/2y),其中x-y=2 (x-y)(2x-y-1) 【(1)/(x-y)+(1)/(x+y)】÷(2x)/(x²-2xy+y²) 先化简,再求值 （1）[(x-y)的平方+（x+y)(x-y)]÷2x 其中X=2010,y=2009 （2)y(x+y)+(x+y)(x-y)-x的平方,先化简，再求值（1）[(x-y)的平方+（x+y)(x-y)]÷2x 其中X=2010,y=2009（2)y(x+y)+(x+y)(x-y)-x的平方,其中x=-2,y=二分 先化简,再求值(x-y/x+y)^2÷(y-x/x^2+2xy+y^2)^2*1/x+y,其中x=-4,y=1 先化简再求值:(x+y)(x-y)+(x^2-2xy+y^2)-(x^2y)^3÷(x^2y)^2,其中x=1,y=2. [(1/9(x+y)^3-2(x+y)^2-2/3(x+y)]÷x+y/3x+y/3x+y是整体..