CAIE Further Paper 1 2022 June — Question 1 6 marks

Exam BoardCAIE
ModuleFurther Paper 1 (Further Paper 1)
Year2022
SessionJune
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicCurve Sketching
TypeSketch with |x| in function
DifficultyStandard +0.8 Part (a) is a standard rational function sketch requiring asymptote identification and basic curve behavior. Part (b) requires understanding the transformation effect of |x| on the graph (creating y-axis symmetry), then solving a modulus inequality involving a rational expression, which demands careful case analysis and sign considerations—more sophisticated than typical A-level pure maths questions but within Further Maths scope.
Spec1.02l Modulus function: notation, relations, equations and inequalities1.02n Sketch curves: simple equations including polynomials

1
  1. Sketch the curve with equation \(\mathrm { y } = \frac { \mathrm { x } + 1 } { \mathrm { x } - 1 }\).
  2. Sketch the curve with equation \(\mathrm { y } = \frac { | \mathrm { x } | + 1 } { | \mathrm { x } | - 1 }\) and find the set of values of x for which \(\frac { | \mathrm { x } | + 1 } { | \mathrm { x } | - 1 } < - 2\).

Question 1:
Part (a):
AnswerMarks Guidance
AnswerMarks Guidance
Graph showing correct axes and asymptotes (vertical asymptote at \(x = 0\), horizontal asymptote at \(y = 0\))B1 Axes and asymptotes correct
Correct branches drawn (curve in first quadrant decreasing from top-left to bottom-right, approaching both asymptotes; corresponding branch in third quadrant)B1 Branches correct
Total: 2
Question 1:
Part 1(b):
AnswerMarks Guidance
AnswerMarks Guidance
Graph symmetrical about \(x = 0\)B1 FT FT from sketch in part (a), symmetrical about \(x = 0\)
Correct shape at \(x = 0\) (reflection not turning point)B1 Correct shape at \(x = 0\) (reflection not turning point)
\(\frac{x +1}{
\(-1 < x < -\frac{1}{3}\), \(\frac{1}{3} < x < 1\)A1
Total: 4
## Question 1:

**Part (a):**

| Answer | Marks | Guidance |
|--------|-------|----------|
| Graph showing correct axes and asymptotes (vertical asymptote at $x = 0$, horizontal asymptote at $y = 0$) | B1 | Axes and asymptotes correct |
| Correct branches drawn (curve in first quadrant decreasing from top-left to bottom-right, approaching both asymptotes; corresponding branch in third quadrant) | B1 | Branches correct |
| | **Total: 2** | |

## Question 1:

**Part 1(b):**

| Answer | Marks | Guidance |
|--------|-------|----------|
| Graph symmetrical about $x = 0$ | B1 FT | FT from sketch in part (a), symmetrical about $x = 0$ |
| Correct shape at $x = 0$ (reflection not turning point) | B1 | Correct shape at $x = 0$ (reflection not turning point) |
| $\frac{|x|+1}{|x|-1} = -2$ leading to $|x| = \frac{1}{3}$ | M1 | Finds critical point(s) |
| $-1 < x < -\frac{1}{3}$, $\frac{1}{3} < x < 1$ | A1 | |
| **Total: 4** | | |

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1
\begin{enumerate}[label=(\alph*)]
\item Sketch the curve with equation $\mathrm { y } = \frac { \mathrm { x } + 1 } { \mathrm { x } - 1 }$.
\item Sketch the curve with equation $\mathrm { y } = \frac { | \mathrm { x } | + 1 } { | \mathrm { x } | - 1 }$ and find the set of values of x for which $\frac { | \mathrm { x } | + 1 } { | \mathrm { x } | - 1 } < - 2$.
\end{enumerate}

\hfill \mbox{\textit{CAIE Further Paper 1 2022 Q1 [6]}}