1. a) By using the substitution u = 4- sin x, or otherwise, find b) Hence, or otherwise, find (Marks available: 6) Answer Answer outline and marking scheme for question: 1 Give yourself marks for mentioning any of the points below: a) u = 4 - sin x, therefore du = (-) cos x dx. Substitute u into the given equation gives: Integrating this gives: Therefore: (4 marks) b) Use u = 2x, therefore 1/2 du = dx Substitute u into the given equation and integrating gives: (2 marks) (Marks available: 6)