AQA C1 2008 June — Question 4 6 marks

Exam BoardAQA
ModuleC1 (Core Mathematics 1)
Year2008
SessionJune
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicCompleting the square and sketching
TypeComplete the square
DifficultyModerate -0.8 This is a straightforward completing-the-square exercise with standard follow-up questions. Part (a) requires a routine algebraic manipulation, part (b) is direct reading from the completed square form, and part (c) tests basic understanding of transformations. All parts are textbook-standard with no problem-solving or novel insight required, making it easier than average.
Spec1.02e Complete the square: quadratic polynomials and turning points1.02w Graph transformations: simple transformations of f(x)

4
  1. Express \(x ^ { 2 } - 3 x + 4\) in the form \(( x - p ) ^ { 2 } + q\), where \(p\) and \(q\) are rational numbers.
    (2 marks)
  2. Hence write down the minimum value of the expression \(x ^ { 2 } - 3 x + 4\).
  3. Describe the geometrical transformation that maps the graph of \(y = x ^ { 2 }\) onto the graph of \(y = x ^ { 2 } - 3 x + 4\).

4(a)
AnswerMarks Guidance
\(\left(x - \frac{3}{2}\right)^2\)B1
\(+ \frac{7}{4}\)B1 2
4(b)
AnswerMarks Guidance
Minimum value is \(\frac{7}{4}\)B1 1
4(c)
AnswerMarks Guidance
Translation (and no other transformation stated)E1
through \(\begin{bmatrix} 3/2 \\ 7/4 \end{bmatrix}\) (or equivalent in words)M1, A1 3
**4(a)**

| $\left(x - \frac{3}{2}\right)^2$ | B1 | | Must have $()^2$, $p = 1.5$ |
| $+ \frac{7}{4}$ | B1 | 2 | $q = 1.75$ |

**4(b)**

| Minimum value is $\frac{7}{4}$ | B1 | 1 | ft their $q$ or correct value |

**4(c)**

| **Translation** (and no other transformation stated) | E1 | | (not shift, move, transformation etc) |
| through $\begin{bmatrix} 3/2 \\ 7/4 \end{bmatrix}$ (or equivalent in words) | M1, A1 | 3 | M1 for one component correct or ft their $p$ or $q$ values CSO; condone 1.5 right and 1.75 up etc |

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4
\begin{enumerate}[label=(\alph*)]
\item Express $x ^ { 2 } - 3 x + 4$ in the form $( x - p ) ^ { 2 } + q$, where $p$ and $q$ are rational numbers.\\
(2 marks)
\item Hence write down the minimum value of the expression $x ^ { 2 } - 3 x + 4$.
\item Describe the geometrical transformation that maps the graph of $y = x ^ { 2 }$ onto the graph of $y = x ^ { 2 } - 3 x + 4$.
\end{enumerate}

\hfill \mbox{\textit{AQA C1 2008 Q4 [6]}}