抽象函数是指没有明确给出具体的函数表达式,只是给出一些特殊关系式的函数,它是中学数学中的一个难点.因为抽象,同学们解题时思维常常受阻,思路难以展开,而高考中又经常出现抽象函数,考查同学们的抽象思维能力.有鉴于此,本文对一类抽象函数进行探究.【例1】函数f:{1,2,3}→{1, Abstract function means that there is no specific function expression given, but only some special relational functions. It is a difficult point in middle school mathematics. Because of abstraction, when students solve problems, their thinking is often obstructed and their ideas are difficult to develop. In college entrance examination, there are often abstract functions that examine the abstract thinking ability of the students. In view of this, this article explores a class of abstract functions. Example 1 Function f: {1,2,3}→{1,