Open Interval


An open interval is an interval that does not include its end points. The open interval {x:a<x<b} is denoted (a,b), although the nonstandard notation ]a,b[ is sometimes also used.

See also

Closed Interval, Half-Closed Interval, Interval, Open Disk, Open Set

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Croft, H. T.; Falconer, K. J.; and Guy, R. K. Unsolved Problems in Geometry. New York: Springer-Verlag, p. 1, 1991.Gemignani, M. C. Elementary Topology. New York: Dover, 1990.

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Open Interval

Cite this as:

Weisstein, Eric W. "Open Interval." From MathWorld--A Wolfram Web Resource.

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