| Exam Board | AQA |
|---|---|
| Module | AS Paper 1 (AS Paper 1) |
| Year | 2023 |
| Session | June |
| Marks | 6 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Completing the square and sketching |
| Type | Transformations of quadratic graphs |
| Difficulty | Moderate -0.8 This is a straightforward AS-level question testing completing the square (routine algebraic manipulation), reading the minimum from vertex form (direct recall), and applying a stretch transformation (standard procedure). All parts are textbook exercises requiring no problem-solving insight, making it easier than average. |
| Spec | 1.02e Complete the square: quadratic polynomials and turning points1.02w Graph transformations: simple transformations of f(x) |
| Answer | Marks | Guidance |
|---|---|---|
| 6(a) | Obtains a = 2 | 1.1b |
| Answer | Marks | Guidance |
|---|---|---|
| Obtains b = 5 | 1.1b | B1 |
| Obtains c = –8 | 1.1b | B1 |
| Subtotal | 3 | |
| Q | Marking instructions | AO |
| Answer | Marks |
|---|---|
| 6(b) | Obtains correct coordinates of |
| Answer | Marks | Guidance |
|---|---|---|
| Condone missing brackets. | 1.1b | B1F |
| Subtotal | 1 | |
| Q | Marking instructions | AO |
| Answer | Marks |
|---|---|
| 6(c) | 1 |
| Answer | Marks | Guidance |
|---|---|---|
| PI by correct answer | 3.1a | M1 |
| Answer | Marks | Guidance |
|---|---|---|
| ISW | 2.2a | A1F |
| Subtotal | 2 | |
| Question 6 Total | 6 | |
| Q | Marking instructions | AO |
Question 6:
--- 6(a) ---
6(a) | Obtains a = 2 | 1.1b | B1 | y = 2(x2 – 10x + 21)
y = 2(x2 – 10x + 25 – 4)
y = 2((x – 5)2 – 4)
y = 2(x – 5)2 – 8
Obtains b = 5 | 1.1b | B1
Obtains c = –8 | 1.1b | B1
Subtotal | 3
Q | Marking instructions | AO | Marks | Typical solution
--- 6(b) ---
6(b) | Obtains correct coordinates of
their minimum point.
FT their b and c
Condone missing brackets. | 1.1b | B1F | (5, –8)
Subtotal | 1
Q | Marking instructions | AO | Marks | Typical solution
--- 6(c) ---
6(c) | 1
Uses a stretch scale factor of
2
−4
FTtheir ,do not FT c = 4
c
PI by correct answer | 3.1a | M1 | − 4 1
s c a l e f a c t o r = =
− 8 2
y = 2(x – 5)2 – 8
1
y = 2 ( x – 5 ) 2 – 8
2
y = ( x – 5 ) 2 – 4
y = x2 – 10x + 21
Deduces their correct equation
using their vertical stretch factor.
ACF
FT their c , do not FT c=4
ISW | 2.2a | A1F
Subtotal | 2
Question 6 Total | 6
Q | Marking instructions | AO | Marks | Typical solution
\begin{enumerate}[label=(\alph*)]
\item The curve $C_1$ has equation $y = 2x^2 - 20x + 42$
Express the equation of $C_1$ in the form
$$y = a(x - h)^2 + c$$
where $a$, $b$ and $c$ are integers.
[3 marks]
\item Write down the coordinates of the minimum point of $C_1$
[1 mark]
\item The curve $C_1$ is mapped onto the curve $C_2$ by a stretch in the $y$-direction.
The minimum point of $C_2$ is at $(5, -4)$
Find the equation of $C_2$
[2 marks]
\end{enumerate}
\hfill \mbox{\textit{AQA AS Paper 1 2023 Q6 [6]}}