Trial and Improvement Method

This lesson can be used for revision for the higher Maths GCSE. The examples are quick and concise with exam style questions, go to GCSE Maths if you need more in-depth explanations.

How to use the trial and improvement method
Example 1: The equation
x³ + 5x = 67
has a solution between 3 and 4.
Use a trial and improvement method to find this solution.
Give your answer correct to one decimal place.

Example 2: The equation x³ - 5x = 60 has a solution between 4 and 5.
Find this solution and give your answer correct to 1 decimal place.
You must show all your working.

Example 3: The equation
x³ - 6x = 72
has a solution between 4 and 5
Use a trial and improvement method to find this solution.
Give your answer correct to one decimal place.

Example 4: The diagram show a cube and a cuboid.
The volume of the cube is 100 cm³ more that the volume of the cuboid.
(a) Show that x³ - 10x = 100
(b) Use a trail and improvement method to find the value of x.
Give your answer correct to one decimal place. Go to next lesson