Paper 2 · Trigonometry ⏱ Tested in 5+ recent exam questions Lesson 1 of 8

Trigonometry 1.1 – Pythagoras theorem

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You’ll learn

  • Find the third side of a right-angled triangle using Pythagoras a² + b² = c²
  • Identify the hypotenuse as the side opposite the right angle — always labelled c
  • Solve Pythagoras with algebraic sides: expand, factorise, and reject negative-length roots
  • Recognise the Pythagorean triples (3, 4, 5), (5, 12, 13) and (9, 40, 41) on sight

Most recent exam questions

  • 2025 P2 Q8(a)(i)
  • 2024 P2 Q10(a)(i)
  • 2024 P2 Q8(b)
  • 2024 P2 Q8(e) — deferred
  • 2023 P2 Q3(a) — deferred

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