Paper 2 · Trigonometry ⏱ Tested in 5+ recent exam questions Lesson 4 of 6

Trigonometry 3.4: Changing the midline

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You’ll learn

  • Read midline, amplitude and period from the general form y = a + b·trig(ct)
  • Write the midline as y = a and the range as [a − |b|, a + |b|]
  • Choose 2π/c or 360°/c for the period based on the question's unit system
  • Sketch graphs like y = −2 − 3 cos 4πt, letting a negative b flip the shape

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