Moderate -0.8 This is a straightforward transformation question requiring recall of standard rules (horizontal stretch factor 1/2 for f(2x), vertical stretch factor 3 for 3f(x)) and routine coordinate calculations. The transformations are basic C2 content with no problem-solving or novel insight required, making it easier than average.
In this question, \(f(x) = x^2 - 5x\). Fig. 4 shows a sketch of the graph of \(y = f(x)\).
\includegraphics{figure_4}
On separate diagrams, sketch the curves \(y = f(2x)\) and \(y = 3f(x)\), labelling the coordinates of their intersections with the axes and their turning points. [4]
Crossing $x$-axis at $0$ and $2.5$ | 1 mark |
Min at $(1.25, -6.25)$ | 1 mark |
Crossing $x$-axis at $0$ and $5$ | 1 mark |
Min at $(2.5, -18.75)$ | 1 mark |
In this question, $f(x) = x^2 - 5x$. Fig. 4 shows a sketch of the graph of $y = f(x)$.
\includegraphics{figure_4}
On separate diagrams, sketch the curves $y = f(2x)$ and $y = 3f(x)$, labelling the coordinates of their intersections with the axes and their turning points. [4]
\hfill \mbox{\textit{OCR MEI C2 2010 Q4 [4]}}