Edexcel P2 2022 January — Question 9

Exam BoardEdexcel
ModuleP2 (Pure Mathematics 2)
Year2022
SessionJanuary
TopicAreas Between Curves

9. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{59c9f675-e7eb-47b9-b233-dfbe1844f792-30_639_929_214_511} \captionsetup{labelformat=empty} \caption{Figure 2}
\end{figure} Figure 2 shows
  • the curve \(C\) with equation \(y = x - x ^ { 2 }\)
  • the line \(l\) with equation \(y = m x\), where \(m\) is a constant and \(0 < m < 1\)
The line and the curve intersect at the origin \(O\) and at the point \(P\).
  1. Find, in terms of \(m\), the coordinates of \(P\). The region \(R _ { 1 }\), shown shaded in Figure 2, is bounded by \(C\) and \(l\).
  2. Show that the area of \(R _ { 1 }\) is $$\frac { ( 1 - m ) ^ { 3 } } { 6 }$$ The region \(R _ { 2 }\), also shown shaded in Figure 2, is bounded by \(C\), the \(x\)-axis and \(l\). Given that the area of \(R _ { 1 }\) is equal to the area of \(R _ { 2 }\)
  3. find the exact value of \(m\).
    \includegraphics[max width=\textwidth, alt={}, center]{59c9f675-e7eb-47b9-b233-dfbe1844f792-33_108_76_2613_1875}
    \includegraphics[max width=\textwidth, alt={}, center]{59c9f675-e7eb-47b9-b233-dfbe1844f792-33_52_83_2722_1850}