The diagram shows the design for a decorative glass panel in the shape of a semicircle with center O O\,O and diameter AOEAOEAOE. The points B B\,B and D D\,D lie on the arc of the semicircle such that the chord BD BD\,BD is parallel to the diameter AEAEAE. A specific section of the glass, a segment labeled RRR, is bounded by the chord BD BD\,BD and the arc BCDBCDBCD. The radius of the semicircle is 8 cm and the angle DOE DOE\,DOE is 0.45 radians.

Show that, to 3 decimal places, the angle BOD BOD\,BOD is 2.242 radians.
Find the area of the shaded glass segment RRR, giving your answer in cm2\text{cm}^2cm2 to one decimal place.
Find the perimeter of the shaded region RRR, giving your answer in cm\text{cm}cm to one decimal place.
317 exam-style questions on OCR (MEI) A Level Maths 1.7 Trigonometry, covering 1.7.1 Solve right-angled triangles, 1.7.2 Definitions of sin, cos and tan for any angle, 1.7.3 Graphs of sin, cos and tan, 1.7.4 Exact values of trig functions (degrees), 1.7.5 Area of a triangle, 1.7.6 Sine and cosine rules, 1.7.7 Identity tan = sin/cos, 1.7.8 Identity sin^2 + cos^2 = 1, 1.7.9 Solve simple trigonometric equations, 1.7.10 Exact values of trig functions (radians) (A-level only), 1.7.11 Inverse trigonometric functions (A-level only), 1.7.12 Radians and degree conversion (A-level only), 1.7.13 Arc length and area of a sector (A-level only), 1.7.14 Small angle approximations (A-level only), 1.7.15 Sec, cosec and cot functions (A-level only), 1.7.16 Graphs of reciprocal trig functions (A-level only), 1.7.17 Pythagorean identities for sec and cosec (A-level only), 1.7.18 Compound angle formulae (A-level only), 1.7.19 Double angle identities (A-level only), 1.7.20 Expressions for a cos θ ± b sin θ (A-level only), 1.7.21 Use identities to solve equations (A-level only), 1.7.22 Proofs involving trigonometric functions (A-level only), 1.7.23 Trig to solve problems in context (A-level only), and 1.7 Trigonometry. Each one has a worked solution and a mark scheme showing where the marks go.