Paper 2 · Trigonometry ⏱ Tested in 2 exam questions since 2017 Lesson 5 of 6

Trigonometry 3.5: Identifying functions from their graph

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You’ll learn

  • Write a graph's equation in the form y = a + b·trig(ct) by decoding four features
  • Compute a = (max + min)/2 and |b| = (max − min)/2 from the graph
  • Pick sin or cos and the sign of b from the starting position and direction
  • Find c = 2π/period, multiplying partial cycles by 2 or 4 to recover the period

Most recent exam questions

  • 2023 P2 Q7(f)
  • 2017 P1 Q9(b)(i)
  • 2017 P1 Q9(b)(ii)

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