# Open Interval

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Related to Open Interval: Open set

## open interval

[′ō·pən ′in·tər·vəl] (mathematics)

An open interval of real numbers, denoted by (

*a,b*), consists of all numbers strictly greater than*a*and strictly less than*b*.McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

The following article is from

*The Great Soviet Encyclopedia*(1979). It might be outdated or ideologically biased.## Open Interval

the set of points between two given points. In other words, if *a* and *b* are the coordinates of the two given points, then the set of points having coordinates *x* such that *a* ≤ *x* ≤ *b* is an open interval. An open interval does not contain its end points and is denoted by (*a, b*). In contrast, the closed interval *[a, b]* contains its end points and consists of the points having coordinates *x* such that *a ≤ x ≤ b*.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.