Edexcel F3 2021 June — Question 8

Exam BoardEdexcel
ModuleF3 (Further Pure Mathematics 3)
Year2021
SessionJune
TopicConic sections

8. The hyperbola \(H\) has equation $$4 x ^ { 2 } - y ^ { 2 } = 4$$
  1. Write down the equations of the asymptotes of \(H\).
  2. Find the coordinates of the foci of \(H\). The point \(P ( \sec \theta , 2 \tan \theta )\) lies on \(H\).
  3. Using calculus, show that the equation of the tangent to \(H\) at the point \(P\) is $$y \tan \theta = 2 x \sec \theta - 2$$ The point \(V ( - 1,0 )\) and the point \(W ( 1,0 )\) both lie on \(H\).
    The point \(Q ( \sec \theta , - 2 \tan \theta )\) also lies on \(H\).
    Given that \(P , Q , V\) and \(W\) are distinct points on \(H\) and that the lines \(V P\) and \(W Q\) intersect at the point \(S\),
  4. show that, as \(\theta\) varies, \(S\) lies on an ellipse with equation $$\frac { x ^ { 2 } } { a ^ { 2 } } + \frac { y ^ { 2 } } { b ^ { 2 } } = 1$$ where \(a\) and \(b\) are integers to be found.
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