What is the trapezoid rule?
- The trapezoidal rule is a numerical method used to find the approximate area enclosed by a curve, the-axis and two vertical lines
- it is also known as ‘trapezoid rule’ and ‘trapezium rule’
- The trapezoidal rule finds an approximation of the area by summing of the areas of trapezoids beneath the curve
- Note that there are trapezoids (also called strips) but function values
- The trapezoidal rule is given in the formula booklet
What else can be asked to do with the trapezoid rule?
- Comparing the true answer with the answer from the trapezoid rule
- This may involve finding the percentage error in the approximation
- The true answer may be given in the question, found from a GDC or from work on integration
Using the trapezoidal rule, find an approximate value for
to 3 decimal places, using .
Given that the area bounded by the curve , the -axis and the lines and is 6.993 to three decimal places, calculate the percentage error in the trapezoidal rule approximation.