正５角形の作図を取り入れた三角関数の授業 : 興味を持って理解を深める授業実践

Regular pentagon - sharing a method of teaching trigonometric functions

Creators Iwamoto Toshihiko

According to our syllabus, first-year students will learn trigonometric ratios and functions. Of those contents, addition formulae and their application are difficult for the students to learn because there seem too many formulae to memorize. What should we do to get them more interested so that they can have a deeper understanding? One of the answers I’ve come up with is a lesson where they work on constructing a regular　pentagon.In order to put it into practice, the first thing to do is to look over the academic literature on the　construction by rulers and compasses. Then, I’ll consider how to make a good use of it. Since there are　various ways to make a regular pentagon, I’ve studied which way is likely to become the most proper in our　classrooms. Furthermore, I’ve checked some materials on mathematics history which make the students feel　more intrigued and realize the significance of the study. And I’ll conclude by referring to how my classes go as　an example.

[ISSN]0387-9232

[NCID]AN00031668