Comparative Analysis of Old and New High School Math Textbooks—Taking "Solving Triangles" in the People's Education Press Version as an Example

Solving Triangles is a relatively important content in high school mathematics textbooks and a popular topic in the college entrance examination. It is not only closely related to theoretical knowledge such as trigonometric functions, but also frequently reflected in real life, with rich practical significance. The "National High School Mathematics Curriculum Standard" (2017 edition) no longer sets solving triangles as a separate chapter, but classifies it as the application of plane vectors, and requires the use of vector methods to prove the sine rule and cosine rule. Therefore, the 2019 new textbook has also made great changes compared with the old textbook in 2004. This article compares the chapter structure, teaching content, example questions, and other aspects of the solving triangles in the new and old textbooks, hoping to find the differences in the content changes of solving triangles in the new and old versions of the textbooks, and help teachers better analyze the textbooks and conduct instructional design, so that students can better master this knowledge.