Edexcel FP2 2010 June — Question 5

Exam BoardEdexcel
ModuleFP2 (Further Pure Mathematics 2)
Year2010
SessionJune
TopicPolar coordinates

5. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{3ff7c42d-40b0-4d59-8716-14de4890ac1b-06_524_750_219_610} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} Figure 1 shows the curves given by the polar equations $$r = 2 , \quad 0 \leqslant \theta \leqslant \frac { \pi } { 2 } ,$$ and $$r = 1.5 + \sin 3 \theta , \quad 0 \leqslant \theta \leqslant \frac { \pi } { 2 }$$
  1. Find the coordinates of the points where the curves intersect. The region \(S\), between the curves, for which \(r > 2\) and for which \(r < ( 1.5 + \sin 3 \theta )\), is shown shaded in Figure 1.
  2. Find, by integration, the area of the shaded region \(S\), giving your answer in the form \(a \pi + b \sqrt { 3 }\), where \(a\) and \(b\) are simplified fractions.