← 2.5 Trigonometry (II)

The radian

Mathematics · Grade 11 · about 40 minutes

One radian is the centre angle at which the arc equals the radius, and pi radians make a half turn.

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  • 8 sections of explanation, worked examples and diagrams
  • 1 practice task with hints and worked answers
  • A quiz that marks itself as you go
  • Your progress kept across every subject you take
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