化简下列分式

a/(a²-1) + (3a+1 )/(a²-1) + (2a+3)/(1-a²)
=(a+3a+1-2a-3)/(a²-1)
=(2a-2)/(a+1)(a-1)
=2/(a+1)

结果为 a+1分之2

a/(a^2-1)+(3a+1)/(a^2-1)-(2a+3)/(a^2-1)
=(a+3a+1-2a-3)/(a^2-1)
=(2a-2)/(a^2-1)
=2/(a+1)

a+1分之2

你题目的意思是不是[a/(a²-1)]+[(3a+1)/(a²-1)]+[(2a+3)/(1-a²)]?

(a/a²-1)+(3a+1/a²-1)-(2a+3/a²-1)=(2a-2/a²-1)=2/a+1

解:原式=a/a^2-1 + 3a+1/a^2-1 + 2a+3/1-a^2
=a/a^2-1 + 3a+1/a^2-1 - 2a+3/a^2-1
=a+3a+1-2a-3/a^2-1
=2a-2/a^2-1
=2(a-1)/(a+1)(a-1)
=2/a+1
PS：“/”代表分数线，应该看的懂吧~~

a+1分之2