HKDSE Mathematics

Compulsory Part

Preface

Version: 2026.1.0
Publication date: 2026-08-27

As the cost of new books in Hong Kong continues to rise, buying textbooks and reference books has placed a growing burden on many students and their families. Hoksi Education Limited therefore created this project to provide high-quality reference books that are free, open, and accessible to all.

This book is one of the project’s first publications. It covers the Compulsory Part of the Hong Kong Diploma of Secondary Education (HKDSE) Mathematics curriculum and is written and published as an open-source textbook. Through open collaboration, we hope to keep improving its content and build a lasting collection of learning resources that genuinely serves Hong Kong students.

Contributing

We welcome contributions from students, teachers, parents, and other readers. Whether you spot an error, can clarify an explanation, want to add an example or exercise, or have another suggestion, your contribution can make this book more accurate and useful.

• No programming experience required: You do not need to install any tools. Use “Report an issue” in the website sidebar or open a GitHub issue. Include the language, chapter or page, the problem you found, and your suggested change. For mathematical or factual errors, please include your working or a source.
• If you are familiar with Git or programming: Use “Edit this page” in the website sidebar, or fork the GitHub repository, edit the relevant .qmd source file, and submit a Pull Request describing your changes.

Licence

The text is licensed under CC BY-NC-SA 4.0. You may copy, adapt, and redistribute it — including for teaching — as long as you credit the source, do not use it for commercial purposes, and share your adaptations under the same licence.

In addition, government, aided, Direct Subsidy Scheme, and private primary and secondary schools in Hong Kong may copy, adapt, and make this work available through school-operated learning platforms for internal teaching purposes, regardless of whether the school charges tuition. All other licence terms, including attribution and ShareAlike, continue to apply.

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