> For the complete documentation index, see [llms.txt](https://easonwang.gitbook.io/trigonometric-functions/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://easonwang.gitbook.io/trigonometric-functions/master.md).

# Introduction

## 記錄一些數學相關

<https://app.gitbook.com/@easonwang/s/trigonometric-functions/>

![https://zh.wikipedia.org/wiki](/files/-MO0Cmn83bewYmlaXqde)