不给出具体解析式,只给出函数的特殊条件或特征的函数即为抽象函数。一般形式为y=f(x),或许还附有定义域、值域等,如,y=f(x),(x>0,y>0)。由于这类问题可以全面考查学生对函数概念和性质的理解,同时抽象函数问题又将函数的定义域、值域、单调性、奇偶性、周期性和图象集于一身,所以在各地高考试题中不断出现;学生在解决这类问题时,往往会感到无从下手,正确率低,本文就这类问题的解法归类如下: Not given a specific analytical expression, only given the special function of the function or feature is the abstract function. The general form is y = f (x), perhaps with a domain, range, etc., for example, y = f (x), (x> 0, y> 0). Because of these problems can fully examine the student’s understanding of the concept and nature of the function, and abstract function problems in turn the function of the domain, range, monotonous, parity, periodic and image set in one, so the college entrance examination questions In the continuous emergence of students in solving such problems, they often feel helpless, the correct rate is low, this paper on the solution of these problems are grouped as follows: