Edexcel AEA 2022 June — Question 4 14 marks

Exam BoardEdexcel
ModuleAEA (Advanced Extension Award)
Year2022
SessionJune
Marks14
PaperDownload PDF ↗
TopicStandard Integrals and Reverse Chain Rule
TypeIntegration with substitution given
DifficultyChallenging +1.2 This is a multi-part integration question requiring differentiation of a composite exponential, solving a polynomial equation, and integration using reverse chain rule. While it involves several steps and the exponential composite function, the techniques are standard A-level methods (product rule, reverse chain rule recognition) with straightforward algebra. The substitution structure is transparent once f'(x) is found, making this moderately above average but not requiring novel insight.
Spec1.07r Chain rule: dy/dx = dy/du * du/dx and connected rates1.08e Area between curve and x-axis: using definite integrals

4.Given that \(\mathrm { f } ( x ) = \mathrm { e } ^ { x ^ { 3 } - 2 x }\)
  1. find \(\mathrm { f } ^ { \prime } ( x )\) The curves \(C _ { 1 }\) and \(C _ { 2 }\) are defined by the functions g and h respectively,where $$\begin{array} { l l } \mathrm { g } ( x ) = 8 x ^ { 3 } \mathrm { e } ^ { x ^ { 3 } - 2 x } & x \in \mathbb { R } , x > 0 \\ \mathrm {~h} ( x ) = \left( 3 x ^ { 5 } + 4 x \right) \mathrm { e } ^ { x ^ { 3 } - 2 x } & x \in \mathbb { R } , x > 0 \end{array}$$
  2. Find the \(x\) coordinates of the points of intersection of \(C _ { 1 }\) and \(C _ { 2 }\) Given that \(C _ { 1 }\) lies above \(C _ { 2 }\) between these points of intersection,
  3. find the area of the region bounded by the curves between these two points.
    Give your answer in the form \(A + B \mathrm { e } ^ { C }\) where \(A , B\) ,and \(C\) are exact real numbers to be found.

4.Given that $\mathrm { f } ( x ) = \mathrm { e } ^ { x ^ { 3 } - 2 x }$
\begin{enumerate}[label=(\alph*)]
\item find $\mathrm { f } ^ { \prime } ( x )$

The curves $C _ { 1 }$ and $C _ { 2 }$ are defined by the functions g and h respectively,where

$$\begin{array} { l l } 
\mathrm { g } ( x ) = 8 x ^ { 3 } \mathrm { e } ^ { x ^ { 3 } - 2 x } & x \in \mathbb { R } , x > 0 \\
\mathrm {~h} ( x ) = \left( 3 x ^ { 5 } + 4 x \right) \mathrm { e } ^ { x ^ { 3 } - 2 x } & x \in \mathbb { R } , x > 0
\end{array}$$
\item Find the $x$ coordinates of the points of intersection of $C _ { 1 }$ and $C _ { 2 }$

Given that $C _ { 1 }$ lies above $C _ { 2 }$ between these points of intersection,
\item find the area of the region bounded by the curves between these two points.\\
Give your answer in the form $A + B \mathrm { e } ^ { C }$ where $A , B$ ,and $C$ are exact real numbers to be found.
\end{enumerate}

\hfill \mbox{\textit{Edexcel AEA 2022 Q4 [14]}}