Express 5sinx+12cosx5 \sin x + 12 \cos x5sinx+12cosx in the form Rsin(x+α)R \sin (x + \alpha)Rsin(x+α), where R>0 R > 0\,R>0 and 0≤α≤900 \leq \alpha \leq 900≤α≤90
Hence find the maximum value of 5sinx+12cosx5 \sin x + 12 \cos x5sinx+12cosx and find, the smallest positive value of x x\,x for which this maximum occurs
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.