On the basis of learning these concepts, we should pay special attention to the relationships between concepts, and the entities that describe these relationships are a lot of theorems and properties. Part of the exam is to examine students' memory, understanding and application of definitions and theorems, so we should really understand the true meaning of each basic concept given in discrete mathematics.
For example, the definition of proposition, five basic conjunctions, principal disjunctive paradigm and principal conjunctive normal form of formula, three inference rules and reduction to absurdity; Definition of five operations of set; The definition of relationship and its four properties; Definition of function (mapping) and several special functions (mapping); Definition of graph, complete graph, simple graph, subgraph and complement graph; The definitions of simple path and basic path in graphs and the isomorphism of two graphs: the definition of tree and minimum spanning tree. Mastering and understanding these concepts is very important for learning discrete mathematics well.