irrational number

noun

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 This irrational number shows up in the craziest places. Rhett Allain, Wired, "Can You Calculate Pi by Drawing a Circle?," 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, "Strange Stars Pulse to the Golden Mean," 10 Mar. 2015 And on this day, math enthusiasts around the world celebrate the irrational number. Francisco Guzman And Saeed Ahmed, CNN, "You don't need to be a mathematician to enjoy these Pi Day food deals," 14 Mar. 2020 Real examples and applications are messy, with ugly roots made of decimals or irrational numbers. Caroline Delbert, Popular Mechanics, "Mathematician Finds Easier Way to Solve Quadratic Equations," 6 Dec. 2019 The vast majority are irrational numbers, never-ending decimals that cannot be written as fractions. Wired, "A Major Proof Shows How to Approximate Numbers Like Pi," 18 Aug. 2019 Consider a quest to approximate various irrational numbers. Leila Sloman, Scientific American, "New Proof Solves 80-Year-Old Irrational Number Problem," 16 Sep. 2019 The vast majority are irrational numbers, never-ending decimals that cannot be written as fractions. Wired, "A Major Proof Shows How to Approximate Numbers Like Pi," 18 Aug. 2019 Many people conceptualize irrational numbers by rounding them to fractions or decimals: estimating π as 3.14, which is equivalent to 157/50, leads to widespread celebration of Pi Day on March 14th. Leila Sloman, Scientific American, "New Proof Solves 80-Year-Old Irrational Number Problem," 16 Sep. 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.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/irrational%20number. Accessed 5 Aug. 2020.

More from Merriam-Webster on irrational number

Britannica.com: Encyclopedia article about irrational number

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