a-1/a²+2a+1与6/a²-1通分

问题描述:

a-1/a²+2a+1与6/a²-1通分

a-1/a²+2a+1
=(a-1)/(a+1)²
=(a-1)²/[(a-1)(a+1)²]
6/a²-1
=6/[(a+1)(a-1)]
=6(a+1)/[(a-1)(a+1)²]