Question

⒈a－1分之a÷﹙a²－1分之a²－a﹚－﹙a－1分之1﹚

Answer 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)