集合是数学中最基本概念之一 ,它是进一步学习其它数学知识的基础和基石 .因此 ,它在高中数学中有比较重要的地位 .但是由于集合的概念比较抽象 ,许多学生在解题过程中会因某种原因而致误 .现剖析如下 :1　忽视空集而致误例 1　已知集合 A ={ x|x2 - 1 =0 } ,B ={ x|ax - 1 =0 Collection is one of the most basic concepts in mathematics. It is the foundation and foundation for further studying other mathematics knowledge. Therefore, it has a more important position in high school mathematics. However, because the concept of collection is relatively abstract, many students are in the process of solving problems. For some reason, it will be mistaken. The analysis is as follows: 1 Ignore the empty set and cause misunderstanding 1 Known set A ={ x|x2 - 1 =0 }, B ={ x|ax - 1 =0