Solve, for 0<x<π0 < x < \pi0<x<π, the equation
(4x−5)(4sin2x−3)=0 (4x - 5)(4\sin^2 x - 3) = 0 (4x−5)(4sin2x−3)=0giving your answers in terms of π\piπ where appropriate.
Solve, for 0<θ<360∘0 < \theta < 360^\circ0<θ<360∘, the equation
11cosθ=3cos2θ+8 11\cos \theta = 3\cos 2\theta + 8 11cosθ=3cos2θ+8giving your answers to one decimal place.
137 exam-style questions on Edexcel A Level Maths Trigonometry and Modelling, covering 7.1 Addition Formulae, 7.2 Double Angle Formulae, 7.3 Solving Trigonometric Equations, 7.4 Simplifying a cos x +- b sin x, 7.5 Proving Trigonometric Identities, and 7.6 Modelling with Trigonometric Functions. Each one has a worked solution and a mark scheme showing where the marks go.