Show that
cos3x≡4cos3x−3cosx \cos 3x \equiv 4\cos^3 x - 3\cos x cos3x≡4cos3x−3cosxHence find, using algebraic integration,
∫0π6cos3x dx \int_{0}^{\frac{\pi}{6}} \cos^3 x \, dx ∫06πcos3xdx864 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.