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5 marksCompound-Angle Formulae

CSEC Additional Mathematics · 2016 · Paper 2 · Question 4(b)

Given cos 30° = √3/2 and sin 45° = √2/2.

Without the use of a calculator, evaluate cos 105°, in surd form, giving your answer in the simplest terms.

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Other parts of this question

  1. 4(a)Calculate the area of the shaded region in terms of x.[4 marks]
  2. 4(c)Prove that the identity sin(θ + α) / (cos θ cos α) = tan θ + tan α.[3 marks]

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