OCR PURE — Question 3 5 marks

Exam BoardOCR
ModulePURE
Marks5
PaperDownload PDF ↗
TopicFunction Transformations
TypeSingle transformation application
DifficultyEasy -1.3 This question tests basic function transformations with straightforward applications: sketching a simple reciprocal function, applying a horizontal translation (standard substitution x→x-2), and finding the image of a point under a vertical stretch. All three parts require only direct recall of transformation rules with no problem-solving or synthesis required.
Spec1.02o Sketch reciprocal curves: y=a/x and y=a/x^21.02w Graph transformations: simple transformations of f(x)

3
  1. Sketch the curve \(y = - \frac { 1 } { x ^ { 2 } }\).
  2. The curve \(y = - \frac { 1 } { x ^ { 2 } }\) is translated by 2 units in the positive \(x\)-direction. State the equation of the curve after it has been translated.
  3. The curve \(y = - \frac { 1 } { x ^ { 2 } }\) is stretched parallel to the \(y\)-axis with scale factor \(\frac { 1 } { 2 }\) and, as a result, the point \(\left( \frac { 1 } { 2 } , - 4 \right)\) on the curve is transformed to the point \(P\). State the coordinates of \(P\).

Question 3:
Part (a):
AnswerMarks Guidance
Curve in both quadrants, correct shape, symmetrical, not touching axis, asymptote the axes, not finiteB1 Curve must be symmetrical, allow slight movement away from asymptote at one end but not more
Part (b):
AnswerMarks Guidance
\(y = -\dfrac{1}{(x-2)^2}\)M1, A1 M1 for \((y=)-\dfrac{1}{(x-2)^2}\) or \((y=)-\dfrac{1}{(x+2)^2}\); A1 fully correct, must include '\(y=\)'
Part (c):
AnswerMarks Guidance
\(\left(\dfrac{1}{2}, -2\right)\)B2 B1 for each coordinate
# Question 3:

## Part (a):
Curve in both quadrants, correct shape, symmetrical, not touching axis, asymptote the axes, not finite | **B1** | Curve must be symmetrical, allow slight movement away from asymptote at one end but not more

## Part (b):
$y = -\dfrac{1}{(x-2)^2}$ | **M1, A1** | M1 for $(y=)-\dfrac{1}{(x-2)^2}$ or $(y=)-\dfrac{1}{(x+2)^2}$; A1 fully correct, must include '$y=$'

## Part (c):
$\left(\dfrac{1}{2}, -2\right)$ | **B2** | B1 for each coordinate

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3
\begin{enumerate}[label=(\alph*)]
\item Sketch the curve $y = - \frac { 1 } { x ^ { 2 } }$.
\item The curve $y = - \frac { 1 } { x ^ { 2 } }$ is translated by 2 units in the positive $x$-direction.

State the equation of the curve after it has been translated.
\item The curve $y = - \frac { 1 } { x ^ { 2 } }$ is stretched parallel to the $y$-axis with scale factor $\frac { 1 } { 2 }$ and, as a result, the point $\left( \frac { 1 } { 2 } , - 4 \right)$ on the curve is transformed to the point $P$.

State the coordinates of $P$.
\end{enumerate}

\hfill \mbox{\textit{OCR PURE  Q3 [5]}}