(x-1)(x+1)
=x(x+1)-(x+1)
=x²+x-x-1
=x²-1
(x-1)(x²+x+1)
=x(x²+x+1)-(x²+x+1)
=x³+x²+x-x²-x-1
=x³-1
明白请采纳,
有新问题请求助,那个，其实我题目还没出完的...等我题目出完您再回答，好吗？请等一等哈...行！