在解答数学一次函数选择题时,某些题目因含有字母,比较抽象,难以进行判断.遇到这种情况,可在已知条件的限定范围内,对题目中的字母赋予特殊值,然后再进行判断.这种解题方法即为特殊值法.下面举例说明如何用特殊值法解一次函数选择题,供同学们参考. 例1 一次函数y=kx+b When answering mathematics function multiple-choice questions, certain topics are relatively abstract because of their containing letters, and it is difficult to judge. In this case, special values ​​can be assigned to the letters in the title within the limits of the known conditions. To make judgments, this problem-solving method is a special value method. The following example illustrates how to use a special value method to solve a function multiple-choice question for students to refer to. Example 1 First-order function y=kx+b