Paper 2 · Trigonometry ⏱ Tested in 2 exam questions since 2015 Lesson 13 of 13

Trigonometry 4.12 – Trig Proof 8

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You’ll learn

  • Prove tan(A + B) = (tan A + tan B)/(1 − tan A tan B) from earlier proofs
  • Start from the definition tan(A + B) = sin(A + B)/cos(A + B)
  • Divide top and bottom by cos A cos B so every ratio collapses to a tan

Most recent exam questions

  • 2022 P2 Q4(a)(i)
  • 2015 P2 Q5(a)

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