CAIE P2 2013 June — Question 6

Exam BoardCAIE
ModuleP2 (Pure Mathematics 2)
Year2013
SessionJune
TopicFixed Point Iteration

6
  1. By sketching a suitable pair of graphs, show that the equation $$3 \mathrm { e } ^ { x } = 8 - 2 x$$ has only one root.
  2. Verify by calculation that this root lies between \(x = 0.7\) and \(x = 0.8\).
  3. Show that this root also satisfies the equation $$x = \ln \left( \frac { 8 - 2 x } { 3 } \right)$$
  4. Use the iterative formula \(x _ { n + 1 } = \ln \left( \frac { 8 - 2 x _ { n } } { 3 } \right)\) to determine this root correct to 3 decimal places. Give the result of each iteration to 5 decimal places.