An artist is designing a corporate logo. The design consists of a sector DOCDOCDOC of a circle with centre OOO and radius ODODOD. This is joined to a major sector AOBEAAOBEAAOBEA of a smaller circle, also with centre OOO and radius OAOAOA. The points AAA and BBB lie on the line segments ODODOD and OCOCOC respectively, such that OOO, AAA, DDD and OOO, BBB, CCC are collinear.
Given that:
Show that AO=7.5 cmAO = 7.5\text{ cm}AO=7.5 cm.
Calculate the perimeter of the logo, in cm, to 3 significant figures.
Calculate the total area of the logo, in cm2\text{cm}^2cm2, to the nearest whole number.
317 exam-style questions on OCR A Level Maths 1.5 Trigonometry, covering 1.5.1 Definitions for all arguments, 1.5.2 Sine and cosine rules, 1.5.3 Area of a triangle, 1.5.4 Radian measure (A-level only), 1.5.5 Small angle approximations (A-level only), 1.5.6 Graphs of basic trigonometric functions, 1.5.7 Exact values in radians (A-level only), 1.5.8 Reciprocal and inverse trigonometric ratios (A-level only), 1.5.9 Graphs of reciprocal and inverse functions (A-level only), 1.5.10 Trigonometric identities, 1.5.11 Further trigonometric identities (A-level only), 1.5.12 Double angle and compound angle formulae (A-level only), 1.5.13 Geometrical proofs of formulae (A-level only), 1.5.14 Harmonic form Rcos / Rsin (A-level only), 1.5.15 Trigonometric equations, 1.5.16 Proof involving trigonometric functions (A-level only), and 1.5.17 Trigonometric functions in context. Each one has a worked solution and a mark scheme showing where the marks go.