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interval notation

Shorthand for a stretch of the number line, e.g. [2, 5).

Interval notation describes the set of real numbers between two endpoints, using parentheses for excluded endpoints and brackets for included ones — (a,b), [a,b], [a,b), (a,b].

Examples

  • [2, 5) is every number from 2 (included) up to but not including 5.

See also

interval notation
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