Show that
4sin3x≡12sinx−16sin3x 4\sin 3x \equiv 12\sin x - 16\sin^3 x 4sin3x≡12sinx−16sin3xHence, solve, for 0≤x<π0 \leq x < \pi0≤x<π,
16sin3x−12sinx−4=0 16 \sin^3 x - 12 \sin x - 4 = 0 16sin3x−12sinx−4=0348 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.