OCR C2 2015 June — Question 3

Exam BoardOCR
ModuleC2 (Core Mathematics 2)
Year2015
SessionJune
TopicRadians, Arc Length and Sector Area

3
\includegraphics[max width=\textwidth, alt={}, center]{6dd10d03-5fe2-4a70-b5a2-03347dff0360-2_576_599_1062_733} The diagram shows a sector \(A O B\) of a circle with centre \(O\) and radius 8 cm . The angle \(A O B\) is 1.2 radians. The points \(C\) and \(D\) lie on \(O A\) and \(O B\) respectively such that \(O C = 5.2 \mathrm {~cm}\) and \(O D = 2.6 \mathrm {~cm} . C D\) is a straight line.
  1. Find the area of the shaded region \(A C D B\).
  2. Find the perimeter of the shaded region \(A C D B\).