Let's see the definition of definite integral
The definition of the definite integral is very ample and difficult to understand:
The definite integral can be defined using a function f(x)  continuous on an interval [a,b]. This [a,b] interval can be divided into n equal sub intervals. Let the length of an interval be Δx and x_{i} be any value from the interval [a,b]. The value of the function at x_{i} is f(x_{i}). Next, we calculate the Riemann sum which is given by the following formula:
If n is increasing, then Δx would become smaller. In mathematical terms: if n→∞, then Δx→0. If the limit exist, we can define definite integral of the continuous function on the interval [a,b] with the followings:
Check the definite integral formula
Now that we saw the definition on definite integral, it's time we show you the definite integral formula. The definite integrals are a very important chapter mathematic analysis. If f(x) is a function which has upper and lower limits (F(a) respectively F(b)), the definite integral can be represented as:
Have a look at the Definite Integral Table
If you have to solve a definite integral which is contained in a definite integral table, you are allowed to take the value of the integral directly from the table, if you know it obviously. This is why it would be beneficial at least to have a look on such tables.
Here is one table:
Properties of definite integrals are very important
The fundamental concepts of definite integrals are also known as definite integral solvers. Solving definite integrals may require to be aware of a series of properties of definite integrals.
Some of these properties are the followings:
 The definite integral represents the limit of a sum.
 If we inverse the limits of the definite integrals, the given integral become negative.
 where p=f(a) and q=f(b).

Using this kind of properties and the table of definite integrals we solve definite integrals.
Definite integral examples and applications
As definite integrals examples, we are going to offer you a series of definite integrals that you must solve.
1.) Evaluate:
2.) Solve:
For this definite integral example, we are going to offer you the solution, so you can take it as a model.
Understandind of Definite Integral Defitintion
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