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 Making matters worse, the golden ratio is another irrational number! Steven Salzberg, Forbes, 18 Apr. 2022 Math enthusiasts and plenty of students know all about the day that celebrates the irrational number that never ends. Alexandra Meeks, CNN, 13 Mar. 2022 The special occasion was first commemorated back in 1988, when physicist Larry Shaw organized the holiday in San Francisco to honor the infinite, irrational number that has been utilized in mathematics and science for thousands of years. Dave Quinn,, 8 Mar. 2022 Next, choose two angle measurements that are an irrational number of degrees (that is, any number of degrees, like pi, that can’t be written as a fraction). Quanta Magazine, 26 Aug. 2021 Continued fractions are approximations; as the height of the tower of numerators and denominators grows, the continued fraction approximation gets closer to the irrational number being approximated. Evelyn Lamb, Popular Mechanics, 23 Feb. 2021 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 See More

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.

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 8 Aug. 2022.

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