# Past Papers’ Solutions | Cambridge International Examinations (CIE) | AS & A level | Mathematics 9709 | Pure Mathematics 2 (P2-9709/02) | Year 2011 | Oct-Nov | (P2-9709/21) | Q#8

Question i. By first expanding cos(2x + x), show that ii. Hence show that Solution i. We are given that and we are required to express as; Therefore; We have the trigonometric identity; From this we can write; Hence; ii. We are required to show that; We have […]