Edexcel F1 2023 June — Question 7

Exam BoardEdexcel
ModuleF1 (Further Pure Mathematics 1)
Year2023
SessionJune
TopicSign Change & Interval Methods
TypeInterval Bisection with Other Methods

7. $$f ( x ) = x ^ { \frac { 3 } { 2 } } + x - 3$$
  1. Show that the equation \(\mathrm { f } ( x ) = 0\) has a root, \(\alpha\), in the interval \([ 1,2 ]\)
    [0pt]
  2. Starting with the interval [1, 2], use interval bisection twice to show that \(\alpha\) lies in the interval [1.25, 1.5]
    1. Determine \(\mathrm { f } ^ { \prime } ( x )\)
    2. Using 1.375 as a first approximation for \(\alpha\), apply the Newton-Raphson process once to \(\mathrm { f } ( x )\) to determine a second approximation for \(\alpha\), giving your answer to 3 decimal places.
      [0pt]
  3. Use linear interpolation once on the interval [1.25,1.5] to obtain a different approximation for \(\alpha\), giving your answer to 3 decimal places.