CAIE P1 2024 November — Question 5 8 marks

Exam BoardCAIE
ModuleP1 (Pure Mathematics 1)
Year2024
SessionNovember
Marks8
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicFunction Transformations
TypeDescribe transformation from graph
DifficultyStandard +0.3 This is a standard function transformation question requiring students to identify and describe transformations from a graph, then express them algebraically. While it involves multiple transformations (3 steps), these are routine AS-level skills with clear visual cues. The algebraic form in part (b) follows directly from part (a), making this slightly easier than average.
Spec1.02w Graph transformations: simple transformations of f(x)1.02x Combinations of transformations: multiple transformations

\includegraphics{figure_5} In the diagram, the graph with equation \(y = \text{f}(x)\) is shown with solid lines and the graph with equation \(y = \text{g}(x)\) is shown with broken lines.
  1. Describe fully a sequence of three transformations which transforms the graph of \(y = \text{f}(x)\) to the graph of \(y = \text{g}(x)\). [6]
  2. Find an expression for g(x) in the form \(af(bx + c)\), where \(a\), \(b\) and \(c\) are integers. [2]

Question 5:

AnswerMarks Guidance
5(a)Reflection [in] y-axis B1 B1
SC B2 for stretch, SF –1, parallel to x-axis.
−1
Translation or shift  
AnswerMarks Guidance
 0 B1* B1 for ‘translation’ and a correct vector/description.
Do not accept ‘left’/’right’.
If two translations then B0 and B0 for the order.
AnswerMarks Guidance
Stretch, factor 2, parallel to y-axisB2,1,0 B2 all correct OE.
B1 any 2 parts correct.
This can be at any point in the sequence.
AnswerMarks Guidance
Correct order and three correctly named transformations onlyDB1 If a fourth transformation is given this mark is not awarded and
no marks are given for the two transformations of the same
type, except where the reflection is described as a stretch.
If any transformation is incorrectly named this cannot be given.
−1 1
If translation is not   or   then DB0 is given.
 0  0
Alternative Solution for first 3 marks
1
Translation or shift  
AnswerMarks Guidance
0B1* B1 for ‘translation’ and correct vector/description.
Reflection [in] y-axisB1 B1 B1 for ‘reflection’, B1 for ‘in y-axis’.
Alternative solutions
There are alternative solutions which can be marked in the same way
−4
e.g. the given stretch, translation  , reflect in x=−2.5
 0 
6
AnswerMarks Guidance
QuestionAnswer Marks

AnswerMarks Guidance
5(b)g(x)=2f(−x−1) or a=2, b=−1, c=−1 B1
function.
a=−2 is B0.
AnswerMarks
B1Second B1 forb=−1 andc=−1.
2
AnswerMarks Guidance
QuestionAnswer Marks
Question 5:
--- 5(a) ---
5(a) | Reflection [in] y-axis | B1 B1 | B1 for reflection B1 mention of y-axis, OE.
SC B2 for stretch, SF –1, parallel to x-axis.
−1
Translation or shift  
 0  | B1* | B1 for ‘translation’ and a correct vector/description.
Do not accept ‘left’/’right’.
If two translations then B0 and B0 for the order.
Stretch, factor 2, parallel to y-axis | B2,1,0 | B2 all correct OE.
B1 any 2 parts correct.
This can be at any point in the sequence.
Correct order and three correctly named transformations only | DB1 | If a fourth transformation is given this mark is not awarded and
no marks are given for the two transformations of the same
type, except where the reflection is described as a stretch.
If any transformation is incorrectly named this cannot be given.
−1 1
If translation is not   or   then DB0 is given.
 0  0
Alternative Solution for first 3 marks
1
Translation or shift  
0 | B1* | B1 for ‘translation’ and correct vector/description.
Reflection [in] y-axis | B1 B1 | B1 for ‘reflection’, B1 for ‘in y-axis’.
Alternative solutions
There are alternative solutions which can be marked in the same way
−4
e.g. the given stretch, translation  , reflect in x=−2.5
 0 
6
Question | Answer | Marks | Guidance
--- 5(b) ---
5(b) | g(x)=2f(−x−1) or a=2, b=−1, c=−1 | B1 | First B1 for a=2 and no additional terms added to the
function.
a=−2 is B0.
B1 | Second B1 forb=−1 andc=−1.
2
Question | Answer | Marks | Guidance
\includegraphics{figure_5}

In the diagram, the graph with equation $y = \text{f}(x)$ is shown with solid lines and the graph with equation $y = \text{g}(x)$ is shown with broken lines.

\begin{enumerate}[label=(\alph*)]
\item Describe fully a sequence of three transformations which transforms the graph of $y = \text{f}(x)$ to the graph of $y = \text{g}(x)$. [6]

\item Find an expression for g(x) in the form $af(bx + c)$, where $a$, $b$ and $c$ are integers. [2]
\end{enumerate}

\hfill \mbox{\textit{CAIE P1 2024 Q5 [8]}}