Edexcel C4 2006 June — Question 6

Exam BoardEdexcel
ModuleC4 (Core Mathematics 4)
Year2006
SessionJune
TopicArea Under & Between Curves

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 \(\frac { 3 } { 2 } \ln 3\).