AQA C2 2006 January — Question 2 5 marks

Exam BoardAQA
ModuleC2 (Core Mathematics 2)
Year2006
SessionJanuary
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicIndefinite & Definite Integrals
TypeTrapezium rule estimation
DifficultyModerate -0.8 This is a straightforward application of the trapezium rule with clear parameters given (five ordinates, four strips). Part (a) requires only substitution into the standard formula with simple function evaluations, and part (b) tests basic understanding that more strips improve accuracy. Below average difficulty as it's purely procedural with no problem-solving or conceptual challenges.
Spec1.09f Trapezium rule: numerical integration

2
  1. Use the trapezium rule with five ordinates (four strips) to find an approximate value for $$\int _ { 0 } ^ { 4 } \frac { 1 } { x ^ { 2 } + 1 } \mathrm {~d} x$$ giving your answer to four significant figures.
  2. State how you could obtain a better approximation to the value of the integral using the trapezium rule.

Question 2(a):
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(h = 1\)B1 PI
Integral \(= \frac{h}{2}\{\ldots\}\)M1 OE summing of areas of the four trapezia. \([0.75+0.35+0.15+0.079\ldots]\)
\(\{\ldots\} = f(0) + f(4) + 2[f(1) + f(2) + f(3)]\)
\(= \left[1 + \frac{1}{17} + 2\left(\frac{1}{2} + \frac{1}{5} + \frac{1}{10}\right)\right]\)A1 Exact or to 3dp values. Condone one numerical slip
Integral \(= 1.329\)A1 CSO. Must be 1.329
Total (a)4
Question 2(b):
AnswerMarks Guidance
Answer/WorkingMarks Guidance
Increase the number of ordinatesE1 OE
Total (b)1
## Question 2(a):

| Answer/Working | Marks | Guidance |
|---|---|---|
| $h = 1$ | B1 | PI |
| Integral $= \frac{h}{2}\{\ldots\}$ | M1 | OE summing of areas of the four trapezia. $[0.75+0.35+0.15+0.079\ldots]$ |
| $\{\ldots\} = f(0) + f(4) + 2[f(1) + f(2) + f(3)]$ | | |
| $= \left[1 + \frac{1}{17} + 2\left(\frac{1}{2} + \frac{1}{5} + \frac{1}{10}\right)\right]$ | A1 | Exact or to 3dp values. Condone one numerical slip |
| Integral $= 1.329$ | A1 | **CSO**. Must be 1.329 |
| **Total (a)** | **4** | |

## Question 2(b):

| Answer/Working | Marks | Guidance |
|---|---|---|
| Increase the number of ordinates | E1 | OE |
| **Total (b)** | **1** | |

---
2
\begin{enumerate}[label=(\alph*)]
\item Use the trapezium rule with five ordinates (four strips) to find an approximate value for

$$\int _ { 0 } ^ { 4 } \frac { 1 } { x ^ { 2 } + 1 } \mathrm {~d} x$$

giving your answer to four significant figures.
\item State how you could obtain a better approximation to the value of the integral using the trapezium rule.
\end{enumerate}

\hfill \mbox{\textit{AQA C2 2006 Q2 [5]}}