irrational number


Definition of irrational number

: a number that can be expressed as an infinite decimal with no set of consecutive digits repeating itself indefinitely and that cannot be expressed as the quotient of two integers

Examples of irrational number in a Sentence

Recent Examples on the Web Take, for example, Pi, which is an irrational number. Popular Mechanics, 21 Feb. 2021 Continued fractions for an irrational number, like Pi, go on ad infinitum. Popular Mechanics, 21 Feb. 2021 With an irrational number, those nested layers will go on forever. Popular Mechanics, 21 Feb. 2021 This irrational number shows up in the craziest places. Rhett Allain, Wired, 13 Mar. 2020 This irrational number, which begins 1.618, is found in certain spirals, golden rectangles and now the relative speeds of two mysterious stellar processes. Quanta Magazine, 10 Mar. 2015 And on this day, math enthusiasts around the world celebrate the irrational number. Francisco Guzman And Saeed Ahmed, CNN, 14 Mar. 2020 Real examples and applications are messy, with ugly roots made of decimals or irrational numbers. Caroline Delbert, Popular Mechanics, 6 Dec. 2019 The vast majority are irrational numbers, never-ending decimals that cannot be written as fractions. Wired, 18 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'irrational number.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of irrational number

1551, in the meaning defined above

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Time Traveler for irrational number

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The first known use of irrational number was in 1551

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Cite this Entry

“Irrational number.” Dictionary, Merriam-Webster, Accessed 17 Jun. 2021.

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