Edexcel C4 — Question 7

Exam BoardEdexcel
ModuleC4 (Core Mathematics 4)
TopicChain Rule

7. \begin{figure}[h]
\captionsetup{labelformat=empty} \caption{Figure 3} \includegraphics[alt={},max width=\textwidth]{a1b078fe-96e3-4d62-bf0d-415294ba022f-6_805_1445_269_230}
\end{figure} The curve \(C\) with equation \(y = 2 \mathrm { e } ^ { x } + 5\) meets the \(y\)-axis at the point \(M\), as shown in Fig. 3 .
  1. Find the equation of the normal to \(C\) at \(M\) in the form \(a x + b y = c\), where \(a , b\) and \(c\) are integers. This normal to \(C\) at \(M\) crosses the \(x\)-axis at the point \(N ( n , 0 )\).
  2. Show that \(n = 14\). The point \(P ( \ln 4,13 )\) lies on \(C\). The finite region \(R\) is bounded by \(C\), the axes and the line \(P N\), as shown in Fig. 3.
  3. Find the area of \(R\), giving your answers in the form \(p + q \ln 2\), where \(p\) and \(q\) are integers to be found.