what is a domain? what is a range?

Since this is not my area of expertise, I searched Google under the key words "domain range math" to get these possible sources:

http://mathforum.org/library/drmath/view/54551.html
http://www.purplemath.com/modules/fcns2.htm
http://www.freemathhelp.com/domain-range.html
http://www.intmath.com/Functions-and-graphs/2a_Domain-and-range.php
http://www.analyzemath.com/DomainRange/DomainRange.html

In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search. Also see http://hanlib.sou.edu/searchtools/.

I hope this helps. Thanks for asking.