《平面三角法讲义》是清末民国时期汉译日本的教科书,该教科书在晚清时期使用较多,其编写具有一定的特色,通过对教材的分析,发现主要有以下特点:知识点涵盖现在高中三角函数所有知识点,略穿插高等数学内容;习题覆盖面较广、层次分明满足学生差异;概念等描述通俗易懂,以基础题巩固知识点。此教科书对当时的中国数学教育产生了特殊的影响,也对现今的三角函数教学有一定的启示。 “Plane Triangular Lecture” is a textbook of the Chinese translation of Japan from the late Qing Dynasty to the Republic of China. The textbook was used in the late Qing Dynasty and its writing has certain characteristics. Through the analysis of the teaching materials, it was found that the main features are as follows: Knowledge points cover the current high school All the knowledge points of the trigonometric function are slightly interspersed with advanced mathematics content; the coverage of the exercises is wide and distinct, and the differences are met to meet student differences; the concepts are easy to understand, and the basic questions are used to consolidate knowledge points. This textbook has had a special influence on Chinese mathematics education at that time, and it also has some enlightenment to the current trigonometric teaching.