【摘要】 讨论了收敛数列的保号性和收敛数列与其子数列间关系的两点注记。指出收敛数列的保号性指的是当n充分大时(因n→∞),xn与其极限必同号。用定义证明了收敛数列与其互补子列收敛性的等价关系.更多还原

【Abstract】 This paper discusses the two notes,one is the nature of maintaining sign of convergent sequences,the other is the relation between convergent sequences and its subsequences.The nature of maintaining sign means xn has the same sign with its limit when n is large enough(for n→∞).The paper proves the equivalence relation of the convergent sequences with its complementary subsequences by using the definition of convergence.更多还原