Edexcel C4 2006 June — Question 6 13 marks

Exam BoardEdexcel
ModuleC4 (Core Mathematics 4)
Year2006
SessionJune
Marks13
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicNumerical integration
TypeCompare two trapezium rule estimates
DifficultyModerate -0.3 This is a standard C4 trapezium rule question with straightforward function evaluation, routine application of the formula with different strip numbers, a conceptual explanation about accuracy, and integration by parts. All components are textbook exercises requiring no novel insight, making it slightly easier than average.
Spec1.08i Integration by parts1.09f Trapezium rule: numerical integration

6. \begin{figure}[h]
\captionsetup{labelformat=empty} \caption{Figure 3} \includegraphics[alt={},max width=\textwidth]{c0c6303b-f527-4e68-91bc-5c9c6ffa8de8-09_442_805_283_555}
\end{figure} Figure 3 shows a sketch of the curve with equation \(y = ( x - 1 ) \ln x , \quad x > 0\).
  1. Complete the table with the values of \(y\) corresponding to \(x = 1.5\) and \(x = 2.5\).
    \(x\)11.522.53
    \(y\)0\(\ln 2\)\(2 \ln 3\)
    Given that \(I = \int _ { 1 } ^ { 3 } ( x - 1 ) \ln x \mathrm {~d} x\),
  2. use the trapezium rule
    1. with values of \(y\) at \(x = 1,2\) and 3 to find an approximate value for \(I\) to 4 significant figures,
    2. with values of \(y\) at \(x = 1,1.5,2,2.5\) and 3 to find another approximate value for \(I\) to 4 significant figures.
  3. Explain, with reference to Figure 3, why an increase in the number of values improves the accuracy of the approximation.
  4. Show, by integration, that the exact value of \(\int _ { 1 } ^ { 3 } ( x - 1 ) \ln x \mathrm {~d} x\) is \(\frac { 3 } { 2 } \ln 3\).

6.

\begin{figure}[h]
\begin{center}
\captionsetup{labelformat=empty}
\caption{Figure 3}
  \includegraphics[alt={},max width=\textwidth]{c0c6303b-f527-4e68-91bc-5c9c6ffa8de8-09_442_805_283_555}
\end{center}
\end{figure}

Figure 3 shows a sketch of the curve with equation $y = ( x - 1 ) \ln x , \quad x > 0$.
\begin{enumerate}[label=(\alph*)]
\item Complete the table with the values of $y$ corresponding to $x = 1.5$ and $x = 2.5$.

\begin{center}
\begin{tabular}{ | c | c | c | c | c | c | }
\hline
$x$ & 1 & 1.5 & 2 & 2.5 & 3 \\
\hline
$y$ & 0 &  & $\ln 2$ &  & $2 \ln 3$ \\
\hline
\end{tabular}
\end{center}

Given that $I = \int _ { 1 } ^ { 3 } ( x - 1 ) \ln x \mathrm {~d} x$,
\item use the trapezium rule
\begin{enumerate}[label=(\roman*)]
\item with values of $y$ at $x = 1,2$ and 3 to find an approximate value for $I$ to 4 significant figures,
\item with values of $y$ at $x = 1,1.5,2,2.5$ and 3 to find another approximate value for $I$ to 4 significant figures.
\end{enumerate}\item Explain, with reference to Figure 3, why an increase in the number of values improves the accuracy of the approximation.
\item Show, by integration, that the exact value of $\int _ { 1 } ^ { 3 } ( x - 1 ) \ln x \mathrm {~d} x$ is $\frac { 3 } { 2 } \ln 3$.
\end{enumerate}

\hfill \mbox{\textit{Edexcel C4 2006 Q6 [13]}}