OCR MEI FP1 2009 January — Question 8 12 marks

Exam BoardOCR MEI
ModuleFP1 (Further Pure Mathematics 1)
Year2009
SessionJanuary
Marks12
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicPolynomial Division & Manipulation
TypeSolving Inequalities with Rational Functions
DifficultyStandard +0.3 This is a routine Further Pure 1 question on rational functions requiring standard techniques: finding intercepts by setting x=0 and y=0, identifying asymptotes from denominator zeros and degree comparison, sketching behavior near asymptotes, and solving an inequality using sign analysis. While it's multi-part with 4 sections, each part follows textbook procedures with no novel insight required. The FP1 context places it slightly above average A-level difficulty, but it remains a standard exercise.
Spec1.02g Inequalities: linear and quadratic in single variable1.02n Sketch curves: simple equations including polynomials

8 Fig. 8 shows part of the graph of \(y = \frac { x ^ { 2 } - 3 } { ( x - 4 ) ( x + 2 ) }\). Two sections of the graph have been omitted. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{35094899-149c-438e-b6c8-b333d2fefc0c-3_725_1025_1160_559} \captionsetup{labelformat=empty} \caption{Fig. 8}
\end{figure}
  1. Write down the coordinates of the points where the curve crosses the axes.
  2. Write down the equations of the two vertical asymptotes and the one horizontal asymptote.
  3. Copy Fig. 8 and draw in the two missing sections.
  4. Solve the inequality \(\frac { x ^ { 2 } - 3 } { ( x - 4 ) ( x + 2 ) } \leqslant 0\).

Question 8(i):
AnswerMarks Guidance
\((\sqrt{3},\ 0),\ (-\sqrt{3},\ 0),\ \left(0,\ \frac{3}{8}\right)\)B1, B1 [2] Intercepts with \(x\) axis (both); intercept with \(y\) axis. SC1 if seen on graph or if \(x=\pm\sqrt{3}\), \(y=3/8\) seen without \(y=0\), \(x=0\) specified
Question 8(ii):
AnswerMarks Guidance
\(x=4,\ x=-2,\ y=1\)B3 [3] Minus 1 for each error. Accept equations written on the graph
Question 8(iii):
AnswerMarks Guidance
*(Graph described)*B1 Correct approaches to vertical asymptotes, LH and RH branches
B1B1LH and RH branches approaching horizontal asymptote
B1 [4]On LH branch \(0
Question 8(iv):
AnswerMarks Guidance
\(-2x\geq\sqrt{3}\)B1 LH interval and RH interval correct (award even if errors in inclusive/exclusive signs)
B2 [3]All inequality signs correct, minus 1 each error
# Question 8(i):

$(\sqrt{3},\ 0),\ (-\sqrt{3},\ 0),\ \left(0,\ \frac{3}{8}\right)$ | B1, B1 [2] | Intercepts with $x$ axis (both); intercept with $y$ axis. SC1 if seen on graph or if $x=\pm\sqrt{3}$, $y=3/8$ seen without $y=0$, $x=0$ specified

# Question 8(ii):

$x=4,\ x=-2,\ y=1$ | B3 [3] | Minus 1 for each error. Accept equations written on the graph

# Question 8(iii):

*(Graph described)* | B1 | Correct approaches to vertical asymptotes, LH and RH branches
 | B1B1 | LH and RH branches approaching horizontal asymptote
 | B1 [4] | On LH branch $0<y<1$ as $x\to-\infty$

# Question 8(iv):

$-2<x\leq-\sqrt{3}$ and $4>x\geq\sqrt{3}$ | B1 | LH interval and RH interval correct (award even if errors in inclusive/exclusive signs)
 | B2 [3] | All inequality signs correct, minus 1 each error

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8 Fig. 8 shows part of the graph of $y = \frac { x ^ { 2 } - 3 } { ( x - 4 ) ( x + 2 ) }$. Two sections of the graph have been omitted.

\begin{figure}[h]
\begin{center}
  \includegraphics[alt={},max width=\textwidth]{35094899-149c-438e-b6c8-b333d2fefc0c-3_725_1025_1160_559}
\captionsetup{labelformat=empty}
\caption{Fig. 8}
\end{center}
\end{figure}

(i) Write down the coordinates of the points where the curve crosses the axes.\\
(ii) Write down the equations of the two vertical asymptotes and the one horizontal asymptote.\\
(iii) Copy Fig. 8 and draw in the two missing sections.\\
(iv) Solve the inequality $\frac { x ^ { 2 } - 3 } { ( x - 4 ) ( x + 2 ) } \leqslant 0$.

\hfill \mbox{\textit{OCR MEI FP1 2009 Q8 [12]}}