【(x+2y)的2次方+(x+2y)(x-2y)】/(2x) 其中x=2,y=2分之1

(y-x)²(x-y)+(x-y)的三次方+2(x-y)²(y-x) (x-y)3次方.(x-y)2次方.(y-x) (x-y)的5次方-(y-x)的2次方, {(z+y)(x-y)-(x-y)的2次方+2y(x-y)}除以4y x-y+x+y分之2y的2次方 y=x的-2次方（x (x-y)的2次方-2(x-y)+(x-y)-5(x-y) (x-y)的四次方(x-y)-2(x-y)²(y-x）³等于? 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/【(x-y)/x】的负二次方 (y-2x)×(2x-2y)的3次方×(y-2x)的4次方 (x+3y)(x-3y)(x的2次方-9y的2次方） (x的2次方-y的2次方-6x-6y)/(x+y) (x—y)的2次方×（x—y)的5次方×（y-x)=() (x-y)的3次方乘(x-y)的2次方乘(y-x) (x-y)的2次方×(y-x)的3次方×（x-y）= x(x-y)-y(y-x)+(x-y)的二次方其中x=-1y=2 (x+y)的2次方(x-y)的2次方-(x-y)(x+y)(x的2次方+y的2次方) 25x的二次方-10x（x-y）+（x-y）的2次方