Given that R=5R = 5R=5 and α=tan−1(43)\displaystyle \alpha = \tan^{-1}\left(\frac{4}{3}\right)α=tan−1(34), where R>0 R > 0\,R>0 and 0≤α≤900 \leq \alpha \leq 900≤α≤90,
Show that f(x)=3cosx−4sinxf(x) = 3 \cos x - 4 \sin xf(x)=3cosx−4sinx
Hence solve, for 0≤x≤3600 \leq x \leq 3600≤x≤360, the equation
3cosx−4sinx=1 3 \cos x - 4 \sin x = 1 3cosx−4sinx=1Give your answers to 1 decimal place.
Write down the minimum value of 3cosx−4sinx3 \cos x - 4 \sin x3cosx−4sinx
Find, to 1 decimal place, the smallest positive value of x x\,x for which this minimum occurs
348 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.