Edexcel F3 2021 June — Question 2 7 marks

Exam BoardEdexcel
ModuleF3 (Further Pure Mathematics 3)
Year2021
SessionJune
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicVolumes of Revolution
TypeSurface area of revolution: Cartesian curve
DifficultyChallenging +1.2 This is a Further Maths question requiring arc length and surface of revolution formulas. Part (a) needs recognizing the curve as a quarter circle and evaluating an integral that simplifies nicely via substitution. Part (b) applies the surface area formula with similar techniques. While these are standard Further Maths topics, they're beyond standard A-level and require careful integration, placing this moderately above average difficulty.
Spec1.08h Integration by substitution4.08d Volumes of revolution: about x and y axes

A curve has equation $$y = \sqrt{9 - x^2} \quad 0 \leq x \leq 3$$
  1. Using calculus, show that the length of the curve is \(\frac{3\pi}{2}\) [4]
The curve is rotated through \(2\pi\) radians about the \(x\)-axis.
  1. Using calculus, find the exact area of the surface generated. [3]

A curve has equation
$$y = \sqrt{9 - x^2} \quad 0 \leq x \leq 3$$

\begin{enumerate}[label=(\alph*)]
\item Using calculus, show that the length of the curve is $\frac{3\pi}{2}$
[4]
\end{enumerate}

The curve is rotated through $2\pi$ radians about the $x$-axis.

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{1}
\item Using calculus, find the exact area of the surface generated.
[3]
\end{enumerate}

\hfill \mbox{\textit{Edexcel F3 2021 Q2 [7]}}