讨论比较2a+1,-3+1的大小

问题描述:

讨论比较2a+1,-3+1的大小

2a+1-(-3+1)
=2a+1-(-2)
=2a+3
2a+3>0时,2a+1>-3+1
a>-3/2
2a+3=0,2a+1=-3+1
a=-3/2
2a+3<0时,2a+1<-3+1
a<-3/2