Paper 2 · Trigonometry
⏱ Tested in 1 exam question since 2023
Lesson 5 of 13
Trigonometry 4.4: Quadratic equations
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- Spot a quadratic-trig equation: mixed angles (cos 2x, sin x) or ratios (sec², tan)
- Unify with an identity, substitute y = trig, factorise, then unit-circle each root
- Discard impossible roots like cos = 2 before the unit-circle step
- Handle half-angles with sin²(½x) = ½(1 − cos x), halving the domain for θ/2
Most recent exam questions
- 2023 P2 Q2(c)
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