Paper 2 · Trigonometry
⏱ Tested in 4 exam questions since 2022
Lesson 2 of 13
Trigonometry 4.1: Compound angle formula
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- Use the six compound-angle formulas on page 14, watching the cos/tan sign flip
- Evaluate sin 75°, cos 105° or tan 15° by splitting into standard angles like 30° + 45°
- Find cos(A − B) from given ratios, recovering missing values with Pythagoras
- Prove identities by expanding one side and cancelling symmetric terms
Most recent exam questions
- 2025 P2 Q7(e) — deferred
- 2024 P2 Q4(a) — deferred
- 2023 P2 Q2(b)
- 2022 P2 Q4(a)(ii)
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