Higher June 2018 Paper 4 Q8
8 A, B, C and D are points on the circumference of a circle, centre O.
Not to scale
Angle CAD = 28° and CD = 6.4 cm.
BD is a diameter of the circle.
Calculate the area of the circle. [5]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| 145.2 to 146.2 | 5 | B1 for angle CBD = 28 soi or for angle BCD = 90 soi and M2 for \(\dfrac{6.4}{\sin 28}\) oe or 13.6[3…] nfww or M1 for \(\sin [28] = \dfrac{6.4}{[..]}\) oe and M1 for \(\pi \times (\textit{their}\text{ radius})^2\) | B1 implied by e.g. 28 or 62 correctly used in trigonometry or 28, 62 or 90 (or symbol) marked in the correct place in the diagram 13.6… can imply B1 however if it is marked on the wrong side, e.g. on AC, then it scores 0 marks |