OCR MEI FP1 2009 June — Question 7 12 marks

Exam BoardOCR MEI
ModuleFP1 (Further Pure Mathematics 1)
Year2009
SessionJune
Marks12
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicPolynomial Division & Manipulation
TypeSketching Rational Functions with Horizontal Asymptote Only
DifficultyStandard +0.3 This is a standard FP1 rational function sketching question requiring routine techniques: finding intercepts (factored form given), identifying asymptotes (vertical from denominators, horizontal from degree comparison), and determining approach behavior using limit analysis. While it involves multiple steps, each is algorithmic with no novel insight required, making it slightly easier than average.
Spec1.02k Simplify rational expressions: factorising, cancelling, algebraic division1.02n Sketch curves: simple equations including polynomials1.02y Partial fractions: decompose rational functions

7 A curve has equation \(y = \frac { ( x + 2 ) ( 3 x - 5 ) } { ( 2 x + 1 ) ( x - 1 ) }\).
  1. Write down the coordinates of the points where the curve crosses the axes.
  2. Write down the equations of the three asymptotes.
  3. Determine whether the curve approaches the horizontal asymptote from above or below for
    (A) large positive values of \(x\),
    (B) large negative values of \(x\).
  4. Sketch the curve.

Question 7(i):
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\((0,10),(-2,0),\left(\frac{5}{3},0\right)\)B1, B1, B1 [3]
Question 7(ii):
AnswerMarks Guidance
Answer/WorkingMarks Guidance
\(x = \frac{-1}{2}\), \(x=1\), \(y=\frac{3}{2}\)B1, B1, B1 [3]
Question 7(iii):
AnswerMarks Guidance
Answer/WorkingMarks Guidance
Large positive \(x\), \(y \to \frac{3}{2}^+\) (e.g. consider \(x=100\))M1, B1 Clear evidence of method required for full marks
Large negative \(x\), \(y \to \frac{3}{2}^-\) (e.g. consider \(x=-100\))B1 [3]
Question 7(iv):
AnswerMarks Guidance
Answer/WorkingMarks Guidance
Curve: 3 branches of correct shapeB1
Asymptotes correct and labelledB1
Intercepts correct and labelledB1 [3]
# Question 7(i):

| Answer/Working | Marks | Guidance |
|---|---|---|
| $(0,10),(-2,0),\left(\frac{5}{3},0\right)$ | B1, B1, B1 **[3]** | |

---

# Question 7(ii):

| Answer/Working | Marks | Guidance |
|---|---|---|
| $x = \frac{-1}{2}$, $x=1$, $y=\frac{3}{2}$ | B1, B1, B1 **[3]** | |

---

# Question 7(iii):

| Answer/Working | Marks | Guidance |
|---|---|---|
| Large positive $x$, $y \to \frac{3}{2}^+$ (e.g. consider $x=100$) | M1, B1 | Clear evidence of method required for full marks |
| Large negative $x$, $y \to \frac{3}{2}^-$ (e.g. consider $x=-100$) | B1 **[3]** | |

---

# Question 7(iv):

| Answer/Working | Marks | Guidance |
|---|---|---|
| Curve: 3 branches of correct shape | B1 | |
| Asymptotes correct and labelled | B1 | |
| Intercepts correct and labelled | B1 **[3]** | |

---
7 A curve has equation $y = \frac { ( x + 2 ) ( 3 x - 5 ) } { ( 2 x + 1 ) ( x - 1 ) }$.
\begin{enumerate}[label=(\roman*)]
\item Write down the coordinates of the points where the curve crosses the axes.
\item Write down the equations of the three asymptotes.
\item Determine whether the curve approaches the horizontal asymptote from above or below for\\
(A) large positive values of $x$,\\
(B) large negative values of $x$.
\item Sketch the curve.
\end{enumerate}

\hfill \mbox{\textit{OCR MEI FP1 2009 Q7 [12]}}