(a-2\1)²(a²+4\1)²(a+2\1)²

问题描述:

(a-2\1)²(a²+4\1)²(a+2\1)²

[(a-1/2)(a+1/2)(a²+1/4)]²
=[(a²-1/4)(a²+1/4)]²
=(a的4次方-1/16)²
=a的8次方-1/8a的4次方+1/256