CAIE P1 2024 June — Question 6 7 marks

Exam BoardCAIE
ModuleP1 (Pure Mathematics 1)
Year2024
SessionJune
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicStandard Integrals and Reverse Chain Rule
TypeCurve transformation after integration
DifficultyStandard +0.3 Part (a) is a straightforward reverse chain rule integration with constant determination from a given point. Part (b) requires applying two transformations sequentially, which is more conceptually demanding than typical P1 questions but still follows standard procedures. The integration itself is routine, and while the transformation combination requires care, it's methodical rather than requiring novel insight.
Spec1.02w Graph transformations: simple transformations of f(x)1.08a Fundamental theorem of calculus: integration as reverse of differentiation

6 A curve passes through the point \(\left( \frac { 4 } { 5 } , - 3 \right)\) and is such that \(\frac { \mathrm { d } y } { \mathrm {~d} x } = \frac { - 20 } { ( 5 x - 3 ) ^ { 2 } }\).
  1. Find the equation of the curve.
  2. The curve is transformed by a stretch in the \(x\)-direction with scale factor \(\frac { 1 } { 2 }\) followed by a translation of \(\binom { 2 } { 10 }\). Find the equation of the new curve. \includegraphics[max width=\textwidth, alt={}, center]{d6976a4b-aecf-43f1-a3f2-bcad37d03585-08_2716_38_143_2009}

Question 6(a):
AnswerMarks Guidance
AnswerMarks Guidance
Integrate to obtain form \(k(5x-3)^{-1}\)\*M1 OE
\(4(5x-3)^{-1}\)A1 Or unsimplified equivalent. Condone absence of \(\ldots + c\) so far.
Substitute \(x = \frac{4}{5}\) and \(y = -3\) to attempt value of \(c\)DM1 DM0 for substituting \(\left(-3, \frac{4}{5}\right)\)
\(y = 4(5x-3)^{-1} - 7\); allow \(f(x)\) or \(f = 4(5x-3)^{-1} - 7\)A1 OE. Condone \(c = -7\) as the final answer providing \(y = \) or \(f(x) = \frac{4}{(5x-3)} + c\) OE is seen earlier. Attempts to write equation in \(y = mx + c\) form scores A0. Do not ISW. Gains max 3/4.
4
Question 6(b):
AnswerMarks Guidance
AnswerMarks Guidance
Carry out stretch by replacing \(x\) by \(2x\) in their equationM1 Award if given as the second transformation. Do not ignore sign errors.
Carry out translation by replacing \(x\) by \(x - 2\) and \(y\) by \(y - 10\)M1 OE. Award if given as the first transformation. Do not ignore sign errors.
\(y = \frac{4}{10x - 23} + 3\)A1 Or similarly simplified equivalent, WWW.
3
## Question 6(a):

| Answer | Marks | Guidance |
|--------|-------|----------|
| Integrate to obtain form $k(5x-3)^{-1}$ | \*M1 | OE |
| $4(5x-3)^{-1}$ | A1 | Or unsimplified equivalent. Condone absence of $\ldots + c$ so far. |
| Substitute $x = \frac{4}{5}$ and $y = -3$ to attempt value of $c$ | DM1 | DM0 for substituting $\left(-3, \frac{4}{5}\right)$ |
| $y = 4(5x-3)^{-1} - 7$; allow $f(x)$ or $f = 4(5x-3)^{-1} - 7$ | A1 | OE. Condone $c = -7$ as the final answer providing $y = $ or $f(x) = \frac{4}{(5x-3)} + c$ OE is seen earlier. Attempts to write equation in $y = mx + c$ form scores A0. Do not ISW. Gains max 3/4. |
| | **4** | |

## Question 6(b):

| Answer | Marks | Guidance |
|--------|-------|----------|
| Carry out stretch by replacing $x$ by $2x$ in their equation | M1 | Award if given as the second transformation. Do not ignore sign errors. |
| Carry out translation by replacing $x$ by $x - 2$ and $y$ by $y - 10$ | M1 | OE. Award if given as the first transformation. Do not ignore sign errors. |
| $y = \frac{4}{10x - 23} + 3$ | A1 | Or similarly simplified equivalent, WWW. |
| | **3** | |
6 A curve passes through the point $\left( \frac { 4 } { 5 } , - 3 \right)$ and is such that $\frac { \mathrm { d } y } { \mathrm {~d} x } = \frac { - 20 } { ( 5 x - 3 ) ^ { 2 } }$.
\begin{enumerate}[label=(\alph*)]
\item Find the equation of the curve.
\item The curve is transformed by a stretch in the $x$-direction with scale factor $\frac { 1 } { 2 }$ followed by a translation of $\binom { 2 } { 10 }$.

Find the equation of the new curve.\\

\includegraphics[max width=\textwidth, alt={}, center]{d6976a4b-aecf-43f1-a3f2-bcad37d03585-08_2716_38_143_2009}
\end{enumerate}

\hfill \mbox{\textit{CAIE P1 2024 Q6 [7]}}