现行高三数学教材(试验本)对函数单调性的求法只采用定义法来求 ,对学生的学习具有一定误导性 ,本文主要是通过用导数方法来求函数的单调性及其单调区间 ,并将两种方法加以比较 ,说明其优越性。 The current high school mathematics textbook (experimental) monotonicity of the function of seeking only use the definition of law to seek, the learning of students with some misleading, this paper is mainly through the derivative method to find the monotonicity of the function and its monotonic range, and Two ways to compare, indicating its superiority.