(1)化简：（1/a+1+1/a-1）/【2a/（a的平方-2a+1）】 这里是不是少一个a =[(a-1)/(a+1)(a-1)+(a+1)/(a+1)(a-1)]×(a-1)²/2a=2a/(a+1)(a-1)×(a-1)²/2a=(a-1)/(a+1)=(a-1)/(a+1) (2)求（1）中化简结果比3/a+1大2时a的值。(a-1)/(a+1)=3/(a+1)+2∴a-1=3+2a+2a=-6
