超简单分式计算 送分了 在线等

解:由题可得:
[(a^2+3)/(a^2-1)]-[(a+1)/(a-1)]+1
=(a^2+3)/(a+1)(a-1) - (a+1)^2/(a+1)(a-1) +(a+1)(a-1)/(a+1)(a-1)
=[a^2+3-(a^2+2a+1)+(a+1)(a-1)]/(a+1)(a-1)
=(a^2+3-a^2-2a-1+a^2-1)/(a+1)(a-1)
=(a^2-2a+1)/(a+1)(a-1)
=(a-1)(a-1)/(a+1)(a-1)
=(a-1)/(a+1)

原式=[(a^2+3)/(a^2-1)]-[(a+1)^2/(a^2-1)]+1
=[(a^2+3-a^2-2a-1)/(a^2-1)]+1
=(-2a+2a)/[(a+1)(a-1)]+1
=[-2(a+1)]/[(a+1)(a-1)]+1
=-2/(a-1)+(a-1)/(a-1)
=(a-3)/(a-1)

简单你留著自己做咯……