[-2(x-y)②]②·(y-x)③
问题描述:
[-2(x-y)②]②·(y-x)③
PS:②、③是二次方和三次方~
答
[-2(x-y)²]²×(y-x)³=4(x-y)④(y-x)③
=-4(x-y)⑦