CAIE P2 2006 June — Question 6

Exam BoardCAIE
ModuleP2 (Pure Mathematics 2)
Year2006
SessionJune
TopicFixed Point Iteration

6
  1. By sketching a suitable pair of graphs, show that there is only one value of \(x\) that is a root of the equation \(x = 9 \mathrm { e } ^ { - 2 x }\).
  2. Verify, by calculation, that this root lies between 1 and 2 .
  3. Show that, if a sequence of values given by the iterative formula $$x _ { n + 1 } = \frac { 1 } { 2 } \left( \ln 9 - \ln x _ { n } \right)$$ converges, then it converges to the root of the equation given in part (i).
  4. Use the iterative formula, with \(x _ { 1 } = 1\), to calculate the root correct to 2 decimal places. Give the result of each iteration to 4 decimal places.