| Exam Board | AQA |
|---|---|
| Module | Paper 1 (Paper 1) |
| Session | Specimen |
| Marks | 8 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Tangents, normals and gradients |
| Type | Increasing/decreasing intervals |
| Difficulty | Standard +0.3 This is a standard quotient rule differentiation followed by routine algebraic manipulation and solving a quadratic inequality. While it requires multiple steps (differentiate, simplify, determine sign conditions, solve inequality), each component is a textbook technique with no novel insight required. The 8 marks reflect length rather than conceptual difficulty, making it slightly above average but well within typical A-level scope. |
| Spec | 1.02g Inequalities: linear and quadratic in single variable1.07r Chain rule: dy/dx = dy/du * du/dx and connected rates |
| Answer | Marks |
|---|---|
| 9(a)(i) | Selects an appropriate |
| Answer | Marks | Guidance |
|---|---|---|
| rule | AO1.1a | M1 |
| Answer | Marks | Guidance |
|---|---|---|
| (no need for simplification) | AO1.1b | A1 |
| (a)(ii) | States clearly that |
| Answer | Marks | Guidance |
|---|---|---|
| dx | AO2.4 | R1 |
| Answer | Marks | Guidance |
|---|---|---|
| dx | AO3.1a | B1 |
| Answer | Marks | Guidance |
|---|---|---|
| positive | AO2.2a | R1 |
| Answer | Marks | Guidance |
|---|---|---|
| slips | AO2.1 | R1 |
| (b) | Solves the correct quadratic |
| Answer | Marks | Guidance |
|---|---|---|
| correct critical values stated) | AO1.1a | M1 |
| Answer | Marks | Guidance |
|---|---|---|
| using set notation | AO1.1b | A1 |
| Total | 8 | |
| Q | Marking Instructions | AO |
Question 9:
--- 9(a)(i) ---
9(a)(i) | Selects an appropriate
routine procedure; evidence
of quotient rule or product
rule | AO1.1a | M1 | dy 2(4x2 7)8x(2x3)
dx (4x2 7)2
Obtains correct derivative
(no need for simplification) | AO1.1b | A1
(a)(ii) | States clearly that
dy
0 y is increasing
dx | AO2.4 | R1 | dy
y is increasing 0
dx
2(4x2 7)8x(2x3)
0
(4x2 7)2
(4x2 7)2 0for all x
2(4x2 7)8x(2x3)0
8x2 1416x2 24x0
4x212x70 (AG)
Forms inequality from ‘their’
dy
0
dx | AO3.1a | B1
Deduces numerator must be
positive | AO2.2a | R1
Considers denominator alone
and sets out clear argument
to justify given inequality AG
Only award this mark if they
have a completely correct
solution, which is clear, easy
to follow and contains no
slips | AO2.1 | R1
(b) | Solves the correct quadratic
inequality
(accept evidence of
factorising, completing the
square, use of formula, or
correct critical values stated) | AO1.1a | M1 | (2x + 7)(2x – 1)
7 1
x ,
2 2
7 1
<x<
2 2
7 1 7 1
Or x , Or x x: x
2 2 2 2
Obtains fully correct answer,
given as an inequality or
using set notation | AO1.1b | A1
Total | 8
Q | Marking Instructions | AO | Marks | Typical Solution
A curve has equation $y = \frac{2x + 3}{4x^2 + 7}$
\begin{enumerate}[label=(\alph*)]
\item
\begin{enumerate}[label=(\roman*)]
\item Find $\frac{dy}{dx}$
[2 marks]
\item Hence show that $y$ is increasing when $4x^2 + 12x - 7 < 0$
[4 marks]
\end{enumerate}
\item Find the values of $x$ for which $y$ is increasing.
[2 marks]
\end{enumerate}
\hfill \mbox{\textit{AQA Paper 1 Q9 [8]}}