Prove the identity sin2x1+cot2x≡2sin3xcosx\displaystyle \frac{\sin 2x}{1 + \cot^2 x} \equiv 2 \sin^3 x \cos x1+cot2xsin2x≡2sin3xcosx
Hence, show that 4sin4θ1+cot22θ=8sin32θcos2θ\displaystyle \frac{4 \sin 4\theta}{1 + \cot^2 2\theta} = 8\sin^3 2\theta \cos 2\theta1+cot22θ4sin4θ=8sin32θcos2θ
Hence, find ∫4sin4θ1+cot22θdθ\displaystyle \int \frac{4 \sin 4\theta}{1 + \cot^2 2\theta} d\theta∫1+cot22θ4sin4θdθ
855 exam-style questions on Edexcel A Level Maths Integration, covering 11.1 Integrating Standard Functions, 11.2 Integrating f(ax + b), 11.3 Using Trigonometric Identities, 11.4 Reverse Chain Rule, 11.5 Integration by Substitution, 11.6 Integration by Parts, 11.7 Partial Fractions, 11.8 Finding Areas, 11.9 The Trapezium Rule, 11.10 Solving Differential Equations, and 11.11 Modelling with Differential Equations. Each one has a worked solution and a mark scheme showing where the marks go.