计算a-1分之a+1乘以a+1分之a的平方-1-1

问题描述:

计算a-1分之a+1乘以a+1分之a的平方-1-1

原式=(a+1)/(a-1)*【(a+1)(a-1)/(a+1)】-1
=a+1-1=a