Question

一道化简题

【a／（a－1）】÷【（a²-a）／（a²-1）】-【1/（a－1）】

Answer 1

[a/(a-1)]/[(a^2-a)/(a^2-1)]-1/(a-1)
=a/(a-1)*(a^2-1)/a(a-1)-1/(a-1)
=a/(a-1)*(a-1)(a+1)/a(a-1)-1/(a-1)
=(a+1)/(a-1)-1/(a-1)
=a/(a-1)

Answer 2

[a/(a-1)]/ [(a²-a）／（a²-1）]-[1/（a－1）]
=[a/(a-1)]/ [a（a-1）/(a-1)(a+1)]-[1/（a－1）]
=(a+1)/ (a-1)-1/(a-1)
=a/(a-1)