Edexcel C4 — Question 3 9 marks

Exam BoardEdexcel
ModuleC4 (Core Mathematics 4)
Marks9
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicNumerical integration
TypeComplete table then apply trapezium rule
DifficultyModerate -0.3 This is a straightforward numerical methods question requiring routine application of the trapezium rule with given x-values. Part (a) involves simple calculator work evaluating e^x cos x at specific points, part (b) is standard trapezium rule application, and part (c) tests basic understanding of concavity. While it requires multiple steps and understanding of when trapezium rule over/underestimates, it involves no problem-solving or novel insight—just methodical execution of a standard technique, making it slightly easier than average.
Spec1.09f Trapezium rule: numerical integration

\includegraphics{figure_2} Figure 2 shows part of the curve with equation $$y = e^x \cos x, \quad 0 \leq x \leq \frac{\pi}{2}.$$ The finite region \(R\) is bounded by the curve and the coordinate axes.
  1. Calculate, to 2 decimal places, the \(y\)-coordinates of the points on the curve where \(x = 0\), \(\frac{\pi}{6}\), \(\frac{\pi}{3}\) and \(\frac{\pi}{2}\). [3]
  2. Using the trapezium rule and all the values calculated in part (a), find an approximation for the area of \(R\). [4]
  3. State, with a reason, whether your approximation underestimates or overestimates the area of \(R\). [2]

Question 3:
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Question 3:
3
\includegraphics{figure_2}

Figure 2 shows part of the curve with equation
$$y = e^x \cos x, \quad 0 \leq x \leq \frac{\pi}{2}.$$

The finite region $R$ is bounded by the curve and the coordinate axes.

\begin{enumerate}[label=(\alph*)]
\item Calculate, to 2 decimal places, the $y$-coordinates of the points on the curve where $x = 0$, $\frac{\pi}{6}$, $\frac{\pi}{3}$ and $\frac{\pi}{2}$. [3]
\item Using the trapezium rule and all the values calculated in part (a), find an approximation for the area of $R$. [4]
\item State, with a reason, whether your approximation underestimates or overestimates the area of $R$. [2]
\end{enumerate}

\hfill \mbox{\textit{Edexcel C4  Q3 [9]}}