Edexcel P4 2021 June — Question 5

Exam BoardEdexcel
ModuleP4 (Pure Mathematics 4)
Year2021
SessionJune
TopicImplicit equations and differentiation

5. A curve has equation $$y ^ { 2 } = y \mathrm { e } ^ { - 2 x } - 3 x$$
  1. Show that $$\frac { \mathrm { d } y } { \mathrm {~d} x } = \frac { 2 y \mathrm { e } ^ { - 2 x } + 3 } { \mathrm { e } ^ { - 2 x } - 2 y }$$ The curve crosses the \(y\)-axis at the origin and at the point \(P\).
    The tangent to the curve at the origin and the tangent to the curve at \(P\) meet at the point \(R\).
  2. Find the coordinates of \(R\).
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