Set is an important concept in modern mathematics, which is not only closely related to many contents of high school mathematics, but also has penetrated into many fields of natural science and is widely used. Mastering collective knowledge is not only the need of mathematics learning itself, but also the essential content of improving mathematics literacy in an all-round way. When entering high school, the first lesson in mathematics is assembly. Because the concept of collective unit is abstract and there are many symbolic terms, the research methods are obviously different from those when learning junior high school mathematics, which makes some students feel difficult to adapt when they are beginners, often leading to mistakes in solving problems, forming thinking obstacles and even affecting the whole senior high school mathematics learning. In order to help students solve this problem, this paper talks about some matters worthy of attention in collective learning for your reference.

First, accurately grasp the concept of set and skillfully use the relationship between set and set to solve specific problems.

Abstract concepts and symbolic terms are the salient features of set units, such as the concepts of intersection, union and complement and their representations, the relationship between sets and elements and their representations, the relationship between sets and representations, the definitions of subsets, proper subset and sets, and so on. These concepts, relationships and representations can be used as the basis, starting point and even breakthrough point to solve the set problem. Therefore, to learn the content of set well, we must accurately grasp the concept of set and skillfully use the relationship between set and set to solve specific problems.

Second, pay attention to understand the nature of the elements of the set, and learn to use the element analysis method to investigate the related problems of the set.

As we all know, a set can be regarded as the sum of some objects, and each object is called an element of this set. The elements in the collection have "three attributes":

(1), certainty: the elements in the set should be certain and cannot be ambiguous.

(2) Reciprocity: The elements in the set should be different from each other, and the same element can only be counted as one in the set.

(3) Disorder: The elements in the set are out of order.

The relationship between sets, the operation of sets and so on are all defined from the perspective of elements. Therefore, when solving the set problem, grasping the characteristics of elements for analysis is equivalent to Petunia grasping the nose.

Third, understand the mathematical thinking method contained in the set problem and master the basic law of solving the set problem.

Bruner said that mastering mathematical thoughts can make mathematics easier to understand and remember, and understanding mathematical thoughts is a "bright road" to the road of migration. There are rich mathematical ideas in the set unit, such as the idea of combining numbers with shapes, the idea of classified discussion, the idea of equivalent transformation, and the idea of opposing what is difficult, which are very active. In the process of learning, paying attention to mining, refining and infiltrating these mathematical ideas can not only effectively master set knowledge and control the solution of set problems, but also have great significance in developing intelligence, cultivating ability and optimizing thinking quality.

Fourth, pay attention to the particularity of empty set, so as to prevent the problem-solving mistakes caused by ignoring the special situation of empty set.

Empty set is a very important special set, which has the function of "empty set is empty, but it does something". In the process of solving problems, we should always pay attention to the possibility of empty sets, otherwise it will easily lead to mistakes in solving problems. We must attach great importance to this.