What is the trapezium rule?
- The trapezium rule is a numerical method of integration used to find the approximate area under a curve
- It can be used when analytical methods of integration won’t work
- It finds an approximation of the area by finding the sum of the areas of trapeziums beneath the curve
- The formula for an estimate of the area when splitting it into n strips (trapezium) is
Underestimate or overestimate?
- Depending on the shape of the curve, the trapezium rule could be an underestimate or overestimate
- The more trapezium strips used the more accurate the estimate
- Calculating the percentage error can tell you how accurate your estimate is
- Using rectangular strips can find the upper and lower bounds of the interval for the trapezium rule
The formula for the trapezium rule is given in the formula booklet.