Paper 2 · Trigonometry
⏱ Tested in 5 exam questions since 2015
Lesson 9 of 9
Trigonometry 2.9: Use the calculator to find the reference angle
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- Find the reference angle with sin⁻¹/cos⁻¹/tan⁻¹ when the ratio isn't on page 13
- Keep an extra decimal place until the final line when the angle has a coefficient
- Solve cos²A = k by taking ±√k — both signs mean all four quadrants, four answers
Most recent exam questions
- 2024 P1 Q8(e)
- 2023 P2 Q8(a)(iii) — deferred
- 2022 P1 Q8(e)
- 2017 P1 Q9(c)
- 2015 P1 Q9(b)
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