lim根号n^2+n+1/3n-2=?

lim根号n^2+n+1/3n-2=? 求1.lim(3n-(3n^2+2n)/(n-1)) 2.lim(8+1/(n+1)) 3.lim根号n(根号(n+1)-根号(n-3)) lim根号n^2+n+1/3n-2 lim(n→∞)(根号n+2-根号n)*根号n-1=? lim(根号(n平方+2n)-根号(n平方-1)) 1、lim n->无穷 根号[(n^4+n+1)-n^2]*(3n+4) lim（n→∞) 根号n+2-根号n+1/根号n+1-根号n lim(1/n+根号1+1/n+根号2+.+1/n+根号n)=?(n趋近于无穷大） 证明lim(n→∞){n-根号下n^2-n}=1/2 数列极限(n为无限大)lim(n+1-根号（n^2+n))= lim(根号（2n+1）+根号n)/（根号（2n）-根号（n+1））=? lim(3^2n+5^n)/(1+9^n)=? lim[(4+7+...+3n+1)/(n^2-n)]= lim(1/n+2/n+3/n+4/n+5/n+……+n/n)=lim(1/n)+lim(2/n)+……+lim(n/n)成立吗?（n趋近于无穷大）为什么不成立? lim （n→+∞)(根号(n+2)-2*(根号n+1)+根号n) lim（n→∞) 根号n+2(根号n+1-根号n-1) lim(n+3)(4-n)/(n-1)(3-2n) lim(n^3+n)/(n^4-3n^2+1)