Paper 2 · Trigonometry
⏱ Tested in 1 exam question since 2021
Lesson 11 of 13
Trigonometry 4.10 – Trig proof 6
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- Prove cos 2A = cos²A − sin²A by setting B = A in the cos(A + B) formula
- Recognise every double-angle formula as a compound-angle formula with B = A
Most recent exam questions
- 2021 P2 Q4(a)(i)
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