real number

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real number

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real number (plural real numbers)

1. (mathematics) The limit of a convergent sequence of rational numbers, whether the limit is a rational number such as 2, -5, or 2/7 or whether the limit is an irrational number such as the square root of two or the circumference of the circle whose radius is one.

   Every integer is a real number, but not vice versa.

   A real number can be regarded abstractly as an equivalence class of Cauchy sequences of real numbers.^WP

2. (computing) A floating-point number.

   Even if you pass sqrt an integer, it returns a real number.

• imaginary number

• complex number

• rational number
• irrational number

• real number line
• real number system

• hyperreal number
• imaginary number
• surreal number
• transfinite number