Edexcel C4 — Question 1

Exam BoardEdexcel
ModuleC4 (Core Mathematics 4)
TopicImplicit equations and differentiation

  1. The curve \(C\) has equation \(5 x ^ { 2 } + 2 x y - 3 y ^ { 2 } + 3 = 0\). The point \(P\) on the curve \(C\) has coordinates \(( 1,2 )\).
    1. Find the gradient of the curve at \(P\).
    2. Find the equation of the normal to the curve \(C\) at \(P\), in the form \(y = a x + b\), where \(a\) and \(b\) are constants.
    \begin{figure}[h]
    \captionsetup{labelformat=empty} \caption{Figure 1} \includegraphics[alt={},max width=\textwidth]{6e307391-198f-4ea9-99ed-6ef184fca0f7-2_674_895_900_392}
    \end{figure} In Fig. 1, the curve \(C\) has equation \(y = \mathrm { f } ( x )\), where $$\mathrm { f } ( x ) = x + \frac { 2 } { x ^ { 2 } } , \quad x > 0$$ The shaded region is bounded by \(C\), the \(x\)-axis and the lines with equations \(x = 1\) and \(x = 2\). The shaded region is rotated through \(2 \pi\) radians about the \(x\)-axis. Using calculus, calculate the volume of the solid generated. Give your answer in the form \(\pi ( a + \ln b )\), where \(a\) and \(b\) are constants.
    (8)