Question

高等数学题目，求答案

高等数学题目，求答案第一项的1.2.4怎么写，过程要详细

Answer 1

(1) n为奇数时，lim<n→∞> an = lim<n→∞> 1/n = 0，
n为偶数时，lim<n→∞> an = lim<n→∞> (1+n)/n = 1,
则该数列无极限。
(2) lim<n→∞> an = lim<n→∞> 1/√(n+1) = 0.
(4) lim<n→∞> an = lim<n→∞> (-1)^(n+1)n/(n^3+1)
= lim<n→∞> (-1)^(n+1)/(n^2+1/n) = 0.