The domain names,,, and are second-level domain names in the Domain Name System of the Internet.They are reserved by the Internet Assigned Numbers Authority (IANA) at the direction of the Internet Engineering Task Force (IETF) as special-use domain names for documentation purposes. The domain names are used widely in books, tutorials, sample ... Interactive Demonstration of Relation, domain and range. Evaluating Functions. Vertical Line Test. Inverse of a Function. Function Worksheets (free pdf's with answer keys on all the topics normally covered in Algebra 1 and Algebra 2) One To One Functions. Composition of Functions. Example Domain. This domain is for use in illustrative examples in documents. You may use this domain in literature without prior coordination or asking for permission. Oct 13, 2021 · Example. This example demonstrates how to support pre-flight requests, such as those with custom headers or methods other than GET and POST. To support custom headers and additional HTTP verbs, use the allowed-methods and allowed-headers sections as shown in the following example.