Paper 2 · Trigonometry ⏱ Tested in 1 exam question since 2020 Lesson 1 of 9

Trigonometry 2.1 – Deriving the unit circle

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You’ll learn

  • Derive that a point on the unit circle at angle A has coordinates (cos A, sin A)
  • Work out the sign of sin, cos and tan in each of the four quadrants
  • Use the CAST diagram to recall which trig function is positive in each quadrant
  • Extend sin and cos beyond 0°–90° using the unit-circle definition

Most recent exam questions

  • 2020 P1 Q8(a)(i)

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