分解因式a³-a²-a-1

问题描述:

分解因式a³-a²-a-1

如果是秦九召算法的话就是a(a(a-1)-1)-1,不然的话就是原式等于a³-a-a²-1=a﹙a²-1﹚-﹙a+1﹚=a﹙a+1﹚﹙a-1﹚-﹙a+1﹚=﹙a+1﹚[a﹙a-1﹚-1]=﹙a+1﹚﹙a²-a-1﹚

a³-a²-a-1=a²(a-2)+a(a-2)+a-2+1=(a²+a+1)(a-2)+1

上楼的你错了,分解因式到最后是不能有加号的
原式等于a³-a-a²-1=a﹙a²-1﹚-﹙a+1﹚=a﹙a+1﹚﹙a-1﹚-﹙a+1﹚=﹙a+1﹚[a﹙a-1﹚-1]=﹙a+1﹚﹙a²-a-1﹚