Improper integral
An improper integral is the limit of a defined integral when one or both endpoint of the integration interval approach a specific non-real number, like +∞ or −∞.
Explanation
In addition, a defined integral is improper when the integrating function of this integral is not continuous over the entire integration interval. Both situations can also occur simultaneously.
Example 1
A formula for pi in which there is an improper integral of the sinc function reads
This allows you to calculate the value π = 3,1415… by numerical integration.