从几个例談起从我們同学的作業、提問、回答問題等几方面,曾經發現一些由於缺乏最低限度的数学的邏輯知識而產生的錯誤,为了促使同学們今后引起这方面的注意,我们來考慮几个例:例1. (?) 这样計算,表面上看起來,好像沒有錯誤,然而sin(1/x)当x→0时,極限不存在,所以把(?)寫成(?)是毫無根据的 From a few examples, we learned from some of our classmates’ assignments, asking questions, and answering questions. We have discovered some mistakes caused by the lack of minimal knowledge about the logic of mathematics. In order to prompt the students to draw attention in this regard, we will Consider a few examples: Example 1. (?) In this way, it seems that there is no error on the surface, but sin(1/x) does not exist when x→0, so writing (?) as (?) is Unfounded