CAIE P3 2024 November — Question 8

Exam BoardCAIE
ModuleP3 (Pure Mathematics 3)
Year2024
SessionNovember
TopicParametric equations

8 The parametric equations of a curve are $$x = \tan ^ { 2 } 2 t , \quad y = \cos 2 t$$ for \(0 < t < \frac { 1 } { 4 } \pi\).
  1. Show that \(\frac { \mathrm { d } y } { \mathrm {~d} x } = - \frac { 1 } { 2 } \cos ^ { 3 } 2 t\).
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  2. Hence find the equation of the normal to the curve at the point where \(t = \frac { 1 } { 8 } \pi\). Give your answer in the form \(y = m x + c\).