Art of Problem Solving
AoPS Online
Math texts, online classes, and more
for students in grades 5-12.
Visit AoPS Online ‚
Books for Grades 5-12 Online Courses
Beast Academy
Engaging math books and online learning
for students ages 6-13.
Visit Beast Academy ‚
Books for Ages 6-13 Beast Academy Online
AoPS Academy
Small live classes for advanced math
and language arts learners in grades 2-12.
Visit AoPS Academy ‚
Find a Physical Campus Visit the Virtual Campus
During AMC testing, the AoPS Wiki is in read-only mode and no edits can be made.

Interval

Revision as of 22:14, 16 August 2013 by MSTang (talk | contribs) (→‎Definition)

Definition

An interval is a range of values. The most common uses of an interval are to specify the domain and range of a function.

Symbols

If an interval has either $($ or $)$ in it, the values at the end are NOT included in the interval.

If an interval has either $[$ or $]$ in it, the values at the end ARE included.

If both endpoints are not included, then the interval is open. If both endpoints are included, then the interval is closed.

Note: The symbols $($ and $)$ are used with $-\infty$ and $\infty,$ by convention

Examples

  • $(2,3)$ means all real numbers between $2$ and $3,$ but not including $2$ or $3.$
  • $[-2,0)$ means all real numbers between $-2$ and $0,$ including $-2,$ but not including $0.$
  • $[5, \infty)$ means all real numbers greater than or equal to $5.$
Retrieved from "https://artofproblemsolving.com/wiki/index.php?title=Interval&oldid=56924"