limx→1 1/(x-1)-2/(x^3-1)

lim(x→1)[1/(x-1)-2/(x^3-1)]=lim(x→1)[(x^2+x+1)/(x-1)(x^2+x+1)-2/(x^3-1)]=lim(x→1)(x^2+x+1-2)/(x-1)(x^2+x+1)=lim(x→1)(x^2+x-1)/(x-1)(x^2+x+1)=1/0=∞会不会数据设置不合理,这样的话极限其实是不存在的,...