化简：[x(x^3y^2)^2-2(x^2y)^3]×(-xy^2)^3先化简再求值：[x^2y^2(x+y)^2-xy^2(x^3+xy^2)]/(1/2x^2y),其中x=1/2,y=1

化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/(x+y)/x 化简3x-2/(x+y)[(x+y)/3x-x-y]÷(x-y)/x 化简 3x(x^2-x-1)-(x+1)(3x^-x) X^3(x-y)+x(y-x) 化简:(x-3y)(x+y)-(x-2y)(x+2y)-(x-y)平方 化简y(x+y)+(x+y)(x-y)-x^2 化简:5(x-y)+2(x+y)-3(x-y) 化简3(x-y)-7(x--y)+2(y-x) x(x-y)2-(y-x)3 [2/3x-2/x+y(x+y/3x-x-y)]/x-y/x 计算2/3x-2/x+y(x+y/3x-x-y)/x-y/x 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/【(x-y)/x】的负二次方 化简(X-2Y)-(Y-3X) 化简：3x（2x+y)-2x(x-y) x是字母x不是乘号 (x+y)-(x-y)^3÷(x-y)(x+y)×2y化简e , 化简：2x-{-3y+[4x-(3x-y]} 3x^2(x-y)+12(y-x)化简 1/(x-y)+1/(x+y)+2x/(x^2+y^2)+4x^3/(x^4+y^4)化简 化简 [(x-y)^2(x+y)^-2/2(x+y)^2(x-y)^-2]^-3