AQA FP1 2010 June — Question 4 8 marks

Exam BoardAQA
ModuleFP1 (Further Pure Mathematics 1)
Year2010
SessionJune
Marks8
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicCurve Sketching
TypeLogarithmic graph for power law
DifficultyModerate -0.8 This is a straightforward data transformation and linear graph question requiring only routine algebraic manipulation (squaring x values), plotting points, drawing a line of best fit, and reading off values. The conceptual demand is low—students simply need to recognize that y = ax² + b becomes linear when plotted against X = x². All steps are mechanical with no problem-solving insight required.
Spec2.02c Scatter diagrams and regression lines

4 The variables \(x\) and \(y\) are related by an equation of the form $$y = a x ^ { 2 } + b$$ where \(a\) and \(b\) are constants.
The following approximate values of \(x\) and \(y\) have been found.
\(\boldsymbol { x }\)2468
\(\boldsymbol { y }\)6.010.518.028.2
  1. Complete the table below, showing values of \(X\), where \(X = x ^ { 2 }\).
  2. On the diagram below, draw a linear graph relating \(X\) and \(y\).
  3. Use your graph to find estimates, to two significant figures, for:
    1. the value of \(x\) when \(y = 15\);
    2. the values of \(a\) and \(b\).
      1. \(\boldsymbol { x }\)2468
        \(\boldsymbol { X }\)
        \(\boldsymbol { y }\)6.010.518.028.2
      2. \includegraphics[max width=\textwidth, alt={}, center]{763d89e4-861a-4754-a93c-d0902987673f-05_771_1586_1772_274}

Question 4:
Part (a):
AnswerMarks Guidance
Answer/WorkingMark Guidance
\(X = 4, 16, 36, 64\)B1 All four values correct
Part (b):
AnswerMarks Guidance
Answer/WorkingMark Guidance
Correct linear graph plotted through pointsB2 B1 for at least 3 points correctly plotted; B2 for good straight line
Part (c)(i):
AnswerMarks Guidance
Answer/WorkingMark Guidance
Read off \(X\) when \(y=15\), then \(x = \sqrt{X}\)M1 Correct method using graph
\(x \approx 4.7\) (accept range ~4.6–4.8)A1 Correct reading
Part (c)(ii):
AnswerMarks Guidance
Answer/WorkingMark Guidance
Gradient \(= a \approx 0.36\) (accept ~0.35–0.37)B1 Correct gradient
Intercept \(= b \approx 5.2\) (accept ~5.0–5.4)B1 Correct intercept
Method shown for finding bothM1
# Question 4:

## Part (a):
| Answer/Working | Mark | Guidance |
|---|---|---|
| $X = 4, 16, 36, 64$ | B1 | All four values correct |

## Part (b):
| Answer/Working | Mark | Guidance |
|---|---|---|
| Correct linear graph plotted through points | B2 | B1 for at least 3 points correctly plotted; B2 for good straight line |

## Part (c)(i):
| Answer/Working | Mark | Guidance |
|---|---|---|
| Read off $X$ when $y=15$, then $x = \sqrt{X}$ | M1 | Correct method using graph |
| $x \approx 4.7$ (accept range ~4.6–4.8) | A1 | Correct reading |

## Part (c)(ii):
| Answer/Working | Mark | Guidance |
|---|---|---|
| Gradient $= a \approx 0.36$ (accept ~0.35–0.37) | B1 | Correct gradient |
| Intercept $= b \approx 5.2$ (accept ~5.0–5.4) | B1 | Correct intercept |
| Method shown for finding both | M1 | |

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4 The variables $x$ and $y$ are related by an equation of the form

$$y = a x ^ { 2 } + b$$

where $a$ and $b$ are constants.\\
The following approximate values of $x$ and $y$ have been found.

\begin{center}
\begin{tabular}{ | c | c | c | c | c | }
\hline
$\boldsymbol { x }$ & 2 & 4 & 6 & 8 \\
\hline
$\boldsymbol { y }$ & 6.0 & 10.5 & 18.0 & 28.2 \\
\hline
\end{tabular}
\end{center}
\begin{enumerate}[label=(\alph*)]
\item Complete the table below, showing values of $X$, where $X = x ^ { 2 }$.
\item On the diagram below, draw a linear graph relating $X$ and $y$.
\item Use your graph to find estimates, to two significant figures, for:
\begin{enumerate}[label=(\roman*)]
\item the value of $x$ when $y = 15$;
\item the values of $a$ and $b$.\\
(a)

\begin{center}
\begin{tabular}{ | l | c | c | c | c | }
\hline
$\boldsymbol { x }$ & 2 & 4 & 6 & 8 \\
\hline
$\boldsymbol { X }$ &  &  &  &  \\
\hline
$\boldsymbol { y }$ & 6.0 & 10.5 & 18.0 & 28.2 \\
\hline
\end{tabular}
\end{center}

(b)\\
\includegraphics[max width=\textwidth, alt={}, center]{763d89e4-861a-4754-a93c-d0902987673f-05_771_1586_1772_274}
\end{enumerate}\end{enumerate}

\hfill \mbox{\textit{AQA FP1 2010 Q4 [8]}}