OCR C3 — Question 2 6 marks

Exam BoardOCR
ModuleC3 (Core Mathematics 3)
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicVolumes of Revolution
TypeVolume with exact answer required
DifficultyStandard +0.3 This is a straightforward volumes of revolution question requiring students to apply the standard formula V = π∫y²dx, simplify the algebraic expression (3x+1)²/x, and integrate term-by-term. While it involves logarithmic integration, this is standard C3 material with no conceptual challenges beyond routine technique application.
Spec1.08d Evaluate definite integrals: between limits4.08d Volumes of revolution: about x and y axes

2.
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The diagram shows the curve with equation \(y = \frac { 3 x + 1 } { \sqrt { x } } , x > 0\).
The shaded region is bounded by the curve, the \(x\)-axis and the lines \(x = 1\) and \(x = 3\).
Find the volume of the solid formed when the shaded region is rotated through four right angles about the \(x\)-axis, giving your answer in the form \(\pi ( a + \ln b )\), where \(a\) and \(b\) are integers.

2.

\begin{center}
\includegraphics[max width=\textwidth, alt={}]{49d985bf-7c94-4a54-88c1-c0084cd94000-1_563_833_532_513}
\end{center}

The diagram shows the curve with equation $y = \frac { 3 x + 1 } { \sqrt { x } } , x > 0$.\\
The shaded region is bounded by the curve, the $x$-axis and the lines $x = 1$ and $x = 3$.\\
Find the volume of the solid formed when the shaded region is rotated through four right angles about the $x$-axis, giving your answer in the form $\pi ( a + \ln b )$, where $a$ and $b$ are integers.\\

\hfill \mbox{\textit{OCR C3  Q2 [6]}}