Paper 2 · Trigonometry ⏱ Tested in 5+ recent exam questions Lesson 2 of 6

Trigonometry 3.2: Changing the amplitude

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You’ll learn

  • Read the amplitude from the coefficient in y = a sin x and set the range [−|a|, |a|]
  • Recognise that amplitude changes neither the period (2π) nor the midline (y = 0)
  • Reflect the graph in the midline when the coefficient is negative
  • Sketch graphs like y = −6 cos x by marking the quarter-period points

Most recent exam questions

  • 2025 P2 Q4(d) — deferred
  • 2025 P2 Q6(b)
  • 2023 P2 Q7(c)
  • 2021 P2 Q9(b)(i)
  • 2017 P1 Q9(b)(i)

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