Paper 2 · Trigonometry ⏱ Tested in 2 exam questions since 2023 Lesson 12 of 13

Trigonometry 4.11 – Trig Proof 7

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You’ll learn

  • Prove sin(A + B) = sin A cos B + cos A sin B via the complementary-angle bridge
  • Convert sin(A + B) to cos[(90° − A) − B] using sin A = cos(90° − A)
  • Apply the cos(A − B) formula, then convert back with the complementary identities

Most recent exam questions

  • 2023 P2 Q2(a)
  • 2023 P2 Q4(a)(i) — deferred

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