⒈a-1分之a÷﹙a²-1分之a²-a﹚-﹙a-1分之1﹚

问题描述:

⒈a-1分之a÷﹙a²-1分之a²-a﹚-﹙a-1分之1﹚

原式=a/(a-1)×(a+1)(a-1)/a(a-1)-1/(a-1)
=a/(a-1)×(a+1)/a-1/(a-1)
=(a+1)/(a-1)-1/(a-1)
=(a+1-1)/(a-1)
=a/(a-1)