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

Numerical solution of equations — practice question

The graph depicts the curve with equation $y = \frac{\ln(2x + 1)}{x + 3}$. This curve includes a maximum point $M$.
(a)[2]

Derive an expression for $\frac{dy}{dx}$.

(b)[2]

Prove that the $x$-coordinate of $M$ obeys $x = \frac{x + 3}{\ln(2x + 1)} - 0.5$.

(c)[2]

Use calculations to demonstrate that the $x$-coordinate of $M$ is between $2.5$ and $3.0$.

(d)[3]

Apply an iterative formula derived from the equation in part (b) to determine the $x$-coordinate of $M$ correct to $4$ significant figures. State each iteration result to $6$ significant figures.

Worked solution & mark scheme

This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: An attempt to apply the quotient rule

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