Special functions like the exponential functions are integreable, the formula for integrating exponential functions is:

Integrating exponential functions using a simple integral rule or integration by substitution 


Not all Exponential functions are integreable in this Form, examples include the Gaussian integral or euler - poisson integral. 
Gaussian or euler - poisson integral 


Other forms of integrals that are not integreable includes exponential functions that are raised to a power of higher order polynomial function with ord

er is greater than one.. Examples of such function include:

The function above can only be integrated by using power series. 

We shall treat all of these integrals in our upcoming topics. 
Below are few examples of integrating exponential functions using the simple integral rule or integration by substitution.. 
Examples :