Edexcel F1 2016 June — Question 6 10 marks

Exam BoardEdexcel
ModuleF1 (Further Pure Mathematics 1)
Year2016
SessionJune
Marks10
PaperDownload PDF ↗
TopicConic sections
TypeRectangular hyperbola normal re-intersection
DifficultyStandard +0.8 This is a Further Maths question on rectangular hyperbolas requiring parametric verification (routine), normal equation derivation (standard differentiation), and finding a re-intersection point (solving a quartic via substitution). The re-intersection requires algebraic manipulation beyond typical A-level, but follows a standard FM1 pattern. Moderately challenging for Further Maths students.
Spec1.02n Sketch curves: simple equations including polynomials1.07m Tangents and normals: gradient and equations

6. The rectangular hyperbola \(H\) has equation \(x y = 25\)
  1. Verify that, for \(t \neq 0\), the point \(P \left( 5 t , \frac { 5 } { t } \right)\) is a general point on \(H\). The point \(A\) on \(H\) has parameter \(t = \frac { 1 } { 2 }\)
  2. Show that the normal to \(H\) at the point \(A\) has equation $$8 y - 2 x - 75 = 0$$ This normal at \(A\) meets \(H\) again at the point \(B\).
  3. Find the coordinates of \(B\).

6. The rectangular hyperbola $H$ has equation $x y = 25$
\begin{enumerate}[label=(\alph*)]
\item Verify that, for $t \neq 0$, the point $P \left( 5 t , \frac { 5 } { t } \right)$ is a general point on $H$.

The point $A$ on $H$ has parameter $t = \frac { 1 } { 2 }$
\item Show that the normal to $H$ at the point $A$ has equation

$$8 y - 2 x - 75 = 0$$

This normal at $A$ meets $H$ again at the point $B$.
\item Find the coordinates of $B$.\\

\begin{center}

\end{center}
\end{enumerate}

\hfill \mbox{\textit{Edexcel F1 2016 Q6 [10]}}