Edexcel C2 2014 June — Question 1 5 marks

Exam BoardEdexcel
ModuleC2 (Core Mathematics 2)
Year2014
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicNumerical integration
TypeComplete table then apply trapezium rule
DifficultyEasy -1.2 This is a straightforward C2 question requiring only basic substitution into a given function and direct application of the trapezium rule formula with provided values. Both parts are routine procedural tasks with no problem-solving or conceptual challenge beyond recall of standard methods.
Spec1.02b Surds: manipulation and rationalising denominators1.09f Trapezium rule: numerical integration

1. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{e6b490c0-80c4-4e15-b587-ac052ee27db7-02_738_1257_274_340} \captionsetup{labelformat=empty} \caption{Figure 1}
\end{figure} Figure 1 shows a sketch of part of the curve with equation \(y = \sqrt { } \left( x ^ { 2 } + 1 \right) , x \geqslant 0\) The finite region \(R\), shown shaded in Figure 1, is bounded by the curve, the \(x\)-axis and the lines \(x = 1\) and \(x = 2\) The table below shows corresponding values for \(x\) and \(y\) for \(y = \sqrt { } \left( x ^ { 2 } + 1 \right)\).
\(x\)11.251.51.752
\(y\)1.4141.8032.0162.236
  1. Complete the table above, giving the missing value of \(y\) to 3 decimal places.
  2. Use the trapezium rule, with all the values of \(y\) in the completed table, to find an approximate value for the area of \(R\), giving your answer to 2 decimal places.

Question 1:
Part (a)
AnswerMarks Guidance
AnswerMark Guidance
At \(x = 1.25\), \(y = 1.601\) (only)B1 cao 1.601 may not be in the table and can score if seen as part of working in (b)
Part (b)
AnswerMarks Guidance
AnswerMark Guidance
\(\frac{1}{2} \times 0.25\) or \(\frac{1}{8}\)B1 For using \(\frac{1}{2} \times 0.25\) or \(\frac{1}{8}\) or equivalent
Structure \(\{\ldots\}\) correctM1 Must contain first \(y\) value plus last \(y\) value; second bracket multiplied by 2 containing remaining \(y\) values. M0 if any \(x\) values used instead of \(y\) values
\(\frac{1}{2} \times 0.25 \times \{1.414 + 2.236 + 2(\text{their } 1.601 + 1.803 + 2.016)\}\)A1ft Correct expression following through candidate's \(y\) value found in part (a)
\(\left\{= \frac{1}{8}(14.49)\right\} = 1.81125\); answer \(1.81\) or awrt \(1.81\)A1
Note: Correct answer only in (b) scores no marks. If required accuracy not seen in (a), full marks can still be scored in (b).
# Question 1:

## Part (a)

| Answer | Mark | Guidance |
|--------|------|----------|
| At $x = 1.25$, $y = 1.601$ (only) | B1 cao | 1.601 may not be in the table and can score if seen as part of working in (b) |

## Part (b)

| Answer | Mark | Guidance |
|--------|------|----------|
| $\frac{1}{2} \times 0.25$ or $\frac{1}{8}$ | B1 | For using $\frac{1}{2} \times 0.25$ or $\frac{1}{8}$ or equivalent |
| Structure $\{\ldots\}$ correct | M1 | Must contain first $y$ value **plus** last $y$ value; second bracket multiplied by 2 containing remaining $y$ values. M0 if any $x$ values used instead of $y$ values |
| $\frac{1}{2} \times 0.25 \times \{1.414 + 2.236 + 2(\text{their } 1.601 + 1.803 + 2.016)\}$ | A1ft | Correct expression following through candidate's $y$ value found in part (a) |
| $\left\{= \frac{1}{8}(14.49)\right\} = 1.81125$; answer $1.81$ or awrt $1.81$ | A1 | |

**Note:** Correct answer only in (b) scores no marks. If required accuracy not seen in (a), full marks can still be scored in (b).

---
1.

\begin{figure}[h]
\begin{center}
  \includegraphics[alt={},max width=\textwidth]{e6b490c0-80c4-4e15-b587-ac052ee27db7-02_738_1257_274_340}
\captionsetup{labelformat=empty}
\caption{Figure 1}
\end{center}
\end{figure}

Figure 1 shows a sketch of part of the curve with equation $y = \sqrt { } \left( x ^ { 2 } + 1 \right) , x \geqslant 0$

The finite region $R$, shown shaded in Figure 1, is bounded by the curve, the $x$-axis and the lines $x = 1$ and $x = 2$

The table below shows corresponding values for $x$ and $y$ for $y = \sqrt { } \left( x ^ { 2 } + 1 \right)$.

\begin{center}
\begin{tabular}{ | c | c | c | c | c | c | }
\hline
$x$ & 1 & 1.25 & 1.5 & 1.75 & 2 \\
\hline
$y$ & 1.414 &  & 1.803 & 2.016 & 2.236 \\
\hline
\end{tabular}
\end{center}
\begin{enumerate}[label=(\alph*)]
\item Complete the table above, giving the missing value of $y$ to 3 decimal places.
\item Use the trapezium rule, with all the values of $y$ in the completed table, to find an approximate value for the area of $R$, giving your answer to 2 decimal places.
\end{enumerate}

\hfill \mbox{\textit{Edexcel C2 2014 Q1 [5]}}