Integration of is another important formula of integral calculus; this integral belongs exponential formulas category and is one of the simplest formula of integration.

The integration of e power x is of the form

Now consider

Using the derivative formula , we have

Integrating both sides of equation (i) with respect to , we have

Since integration and differentiation are reverse processes to each other , so the integral sign and on the right side will cancel each other, i.e.

__Example__**:** Evaluate the integral with respect to

We have integral

Using integration of e power x, we have