Every page is published as soon as it is written, so that readers can use it and report errors early. Each page shows its status, so you always know how far it has been checked.
What the statuses mean¶
| Status | What it means | Checks that a page has passed |
|---|---|---|
| Draft | Written, but not yet checked. It may contain errors. | The site builds, and the page’s metadata is valid. |
| Reviewed | The mathematics has been read and approved by the maintainer. | Every proof has been checked against a written checklist, and at least half of the worked examples and exercises have a computer check that passes. Every page it builds on is at least reviewed. |
| Verified | Every computation has been checked by a computer, and the proofs have been reviewed twice. | Every worked example and every exercise answer is checked by the computer algebra system SymPy, or, for a proof, by a person. The proofs have been checked by the maintainer and by a second reviewer. No proof relies on a result that comes later. Every page it builds on is at least reviewed. |
A draft page carries a banner warning that it may contain errors.
Keeping verified pages verified¶
Any change to the mathematics of a verified page (a statement, a proof, an example or an answer) has to pass the same checks again; otherwise the page goes back to reviewed. Corrections of mathematical errors in verified pages are logged publicly on the errata page.
Pages by status¶
The tables below are generated from the curriculum and the pages themselves each time the site is built, so they always match the published pages. A planned topic is one that is in the curriculum but not written yet.
Calculus¶
| Chapter | Planned | Draft | Reviewed | Verified |
|---|---|---|---|---|
| 1. Preliminaries | 12 | 0 | 5 | 0 |
| 2. Limits | 7 | 0 | 7 | 0 |
| 3. Continuity | 4 | 0 | 0 | 0 |
| 4. Derivatives | 10 | 0 | 0 | 0 |
| 5. Applications of Derivatives | 10 | 0 | 0 | 0 |
| 6. Integrals | 7 | 0 | 0 | 0 |
| 7. Integration Techniques | 6 | 0 | 0 | 0 |
| 8. Applications of Integrals | 6 | 0 | 0 | 0 |
| 9. Improper Integrals | 3 | 0 | 0 | 0 |
| 10. Sequences and Series | 11 | 0 | 0 | 0 |
| 11. Introduction to Differential Equations | 6 | 0 | 0 | 0 |
| All chapters | 82 | 0 | 12 | 0 |
| Page | Chapter | Status |
|---|---|---|
| Real Numbers and Intervals | 1. Preliminaries | reviewed |
| Absolute Value and Inequalities | 1. Preliminaries | reviewed |
| Functions and Their Graphs | 1. Preliminaries | reviewed |
| Polynomial and Rational Functions | 1. Preliminaries | reviewed |
| Trigonometric Functions | 1. Preliminaries | reviewed |
| The Limit of a Function | 2. Limits | reviewed |
| One-Sided Limits | 2. Limits | reviewed |
| Limit Laws | 2. Limits | reviewed |
| Computing Limits Algebraically | 2. Limits | reviewed |
| The Squeeze Theorem | 2. Limits | reviewed |
| Infinite Limits and Vertical Asymptotes | 2. Limits | reviewed |
| Limits at Infinity and Horizontal Asymptotes | 2. Limits | reviewed |