2a+2/a-1÷(a+1)+a²-1/a²-2a+1
=2（a+1）/(a-1)÷（a+1）+(a+1)(a-1)/(a-1)²
=2/(a-1)+(a+1)/(a-1)
=(a+3)/(a-1)
=3/-1
=-3
如果本题有什么不明白可以追问,