Edexcel Mathematics October 2021 · Paper 1 · Question 10 · ExamRizz

ExamRizzEdexcel MathematicsMathematics

October 2021 · Paper 1 · Question 10 · 8 marks

10. In this question you should show all stages of your working. Solutions relying entir ely on calculator technology are not acceptable. (a) Given that 1 + cos 2θ + sin 2θ ≠ 0 prove that 1c os2s in2tan1c os2s in2θθθθθ−+≡++ (4) (b) Hence solve, for 0 < x < 180° 14 4 14 432−+ ++=coss in coss insinxx xxx giving your answers to one decimal place where appropriate. (4) 31 32 33

Lesson: Definitions of Sine, Cosine and Tangent and Exact Values