Applying the Cosine Rule to find sides and angles

What this note covers

1. What Is the Cosine Rule and When Do You Use It?
2. The Cosine Rule: Both Forms and How to Derive Them
3. Finding an Unknown Side (SAS) — Worked Example
4. Finding an Unknown Angle (SSS) — Worked Example
5. Applied Example — Navigation / Real-World Context
6. Choosing Between the Cosine Rule and the Sine Rule
7. HSC Exam Technique and Common Pitfalls

7 sections · 12 key terms & formulas · 6 common mistakes