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Trigonometry

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Question 2
a.

Show that the equation

5cos⁡2x=3(1+sin⁡x) 5 \cos^2 x = 3(1 + \sin x) 5cos2x=3(1+sinx)

can be written as

5sin⁡2x+3sin⁡x−2=0. 5 \sin^2 x + 3 \sin x - 2 = 0. 5sin2x+3sinx−2=0.
[2]
b.

Hence solve, for 0≤x<360∘0 \leq x < 360^\circ0≤x<360∘, the equation

5cos⁡2x=3(1+sin⁡x), 5 \cos^2 x = 3(1 + \sin x), 5cos2x=3(1+sinx),

giving your answers to 1 decimal place where appropriate.

[5]

Trigonometry Questions

  1. A Level
  2. /Old Maths
  3. /Trigonometry

Practise Edexcel A Level Old Maths Trigonometry with exam-style questions for A Level Old Maths. 14 questions, matched to the Edexcel A Level Old Maths (9371) specification and written in Unit exams C1, C2, C3 and C4 plus two applied units (e.g. S1 and M1) style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.

Question bank