Integration can be used to find areas, volumes, central points and many useful things. Let's learn about definite integrals in A-Level Maths.
Definite Integral
A Definite Integral has start and end values: in other words there is an interval [a, b].
a and b (called limits, bounds or boundaries) are put at the bottom and top of the "S", like this:

There are 3 stages to find the Definite Integral by calculating the Indefinite Integral at a, and at b…

1. The statement. Basically the function written out, with values for a and b

2. After integration. The function is integrated and put into square brackets

3. The evaluation. Round brackets are used to split the integration in two. One part for b and one for a.
Example Question

Evaluate the above ⬆️

Integrate the function and put it in square brackets. Put the ‘limits’ outside thebracket.

Example Question

The Indefinite Integral is: ∫cos(x) dx = sin(x) + C

Example Question


Drafted by Eunice (Maths)
Reference
https://www.mathsisfun.com/calculus/integration-definite.html