Edexcel Mathematics June 2018 · Paper 2 · Question 9 · ExamRizz

ExamRizzEdexcel MathematicsMathematics

June 2018 · Paper 2 · Question 9 · 5 marks

9. Given that θ is measure d in radians, prove, from first principles, that ()dcoss indθ θθ=− You may assume the formula for cos (A ± B) and that as h → 0, sinh h → 1 and cosh h−1 → 0 (5) 25