Edexcel CP2 2022 June — Question 7

Exam BoardEdexcel
ModuleCP2 (Core Pure 2)
Year2022
SessionJune
TopicPolar coordinates

7. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{33292670-3ad0-4125-a3bb-e4b7b21ed5f4-22_678_776_248_639} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} Figure 1 shows a sketch of the curve \(C\) with equation $$r = 1 + \tan \theta \quad 0 \leqslant \theta < \frac { \pi } { 3 }$$ Figure 1 also shows the tangent to \(C\) at the point \(A\).
This tangent is perpendicular to the initial line.
  1. Use differentiation to prove that the polar coordinates of \(A\) are \(\left( 2 , \frac { \pi } { 4 } \right)\) The finite region \(R\), shown shaded in Figure 1, is bounded by \(C\), the tangent at \(A\) and the initial line.
  2. Use calculus to show that the exact area of \(R\) is \(\frac { 1 } { 2 } ( 1 - \ln 2 )\)