a-2/a²-1÷(a-1-(2a-1)/a+1计算

问题描述:

a-2/a²-1÷(a-1-(2a-1)/a+1计算

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