Edexcel P1 2024 January — Question 10

Exam BoardEdexcel
ModuleP1 (Pure Mathematics 1)
Year2024
SessionJanuary
TopicChain Rule

  1. In this question you must show all stages of your working.
The curve \(C\) has equation \(y = \mathrm { f } ( x ) , x > 0\)
Given that
  • the point \(P ( 2,8 \sqrt { 2 } )\) lies on \(C\)
  • \(\mathrm { f } ^ { \prime } ( x ) = 4 \sqrt { x ^ { 3 } } + \frac { k } { x ^ { 2 } }\) where \(k\) is a constant
  • \(\mathrm { f } ^ { \prime \prime } ( x ) = 0\) at \(P\)
    1. find the exact value of \(k\),
    2. find \(\mathrm { f } ( x )\), giving your answer in simplest form.