Editing Category:Irrational numbers (section)

{{Cat main|Irrational number}}
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In [[mathematics]], an '''[[irrational number]]''' is any [[real number]] that is not a [[rational number]], i.e., one that cannot be written as a [[rational fraction|fraction]] ''a'' / ''b'' with ''a'' and ''b'' [[integer]]s and ''b'' not zero.  This is also known as being ''incommensurable'', or without common measure. The irrational numbers are precisely those numbers whose expansion in any given base (decimal, binary, etc.) never ends and never enters a periodic pattern. "Almost all" real numbers are irrational, in a sense which is defined more precisely below.

[[Category:Real numbers]]
[[Category:Numbers]]
[[Category:Sets of real numbers]]