OCR MEI C3 2007 June — Question 2 3 marks

Exam BoardOCR MEI
ModuleC3 (Core Mathematics 3)
Year2007
SessionJune
Marks3
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicComposite & Inverse Functions
TypeFind composite function expression
DifficultyEasy -1.2 This is a straightforward composite function question requiring only direct substitution (gf(x) = |1-x|) and sketching two simple graphs (a linear function and a V-shaped absolute value function). It tests basic recall of composite functions and absolute value with minimal problem-solving, making it easier than average.
Spec1.02l Modulus function: notation, relations, equations and inequalities1.02u Functions: definition and vocabulary (domain, range, mapping)

2 Given that \(\mathrm { f } ( x ) = 1 - x\) and \(\mathrm { g } ( x ) = | x |\), write down the composite function \(\mathrm { gf } ( x )\).
On separate diagrams, sketch the graphs of \(y = \mathrm { f } ( x )\) and \(y = \mathrm { gf } ( x )\).

Question 2:
AnswerMarks Guidance
\(\text{gf}(x) =1-x \)
Sketch of \(y = f(x)\): straight line through \((0,1)\) and \((1,0)\)B1 Correct line
Sketch of \(y = \text{gf}(x)\): V-shape with vertex at \((1,0)\), passing through \((0,1)\)B1 [3] Correct V-shape
# Question 2:

| $\text{gf}(x) = |1-x|$ | B1 | Correct composite function |
| Sketch of $y = f(x)$: straight line through $(0,1)$ and $(1,0)$ | B1 | Correct line |
| Sketch of $y = \text{gf}(x)$: V-shape with vertex at $(1,0)$, passing through $(0,1)$ | B1 | [3] Correct V-shape |

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2 Given that $\mathrm { f } ( x ) = 1 - x$ and $\mathrm { g } ( x ) = | x |$, write down the composite function $\mathrm { gf } ( x )$.\\
On separate diagrams, sketch the graphs of $y = \mathrm { f } ( x )$ and $y = \mathrm { gf } ( x )$.

\hfill \mbox{\textit{OCR MEI C3 2007 Q2 [3]}}