Mathematics 9709 · AS & A Level · Numerical solution of equations

Numerical solution of equations — practice question

(a(i))[2]

Show by drawing a suitable pair of graphs that the equation $e^{2x} = 2 - x$ has only one root.

(a(ii))[2]

Verify by calculation that this root lies between $x = 0$ and $x = 0.5$.

(a(iii))[1]

Show that, if a sequence of values produced by the iterative formula $x_{n+1} = \tfrac{1}{2}\ln(2 - x_n)$ converges, then its limit is the root of the equation in part (i).

(a(iv))[3]

Use this iterative formula, with initial value $x_1 = 0.25$, to find the root correct to $2$ decimal places. State the value from each iteration to $4$ decimal places.

Worked solution & mark scheme

This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: Sketch a recognisable graph that is suitable, for example $y=2-x$

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI