Division sign

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÷
Division sign
In UnicodeU+00F7 ÷ DIVISION SIGN (HTML ÷ · ÷, ÷)
Related
See alsoU+00D7 × MULTIPLICATION SIGN
Different from
Different fromU+2052 COMMERCIAL MINUS SIGN
U+002B + PLUS SIGN
U+2020 DAGGER

The division sign ÷ is a symbol consisting of a short horizontal line with a dot above and another dot below, used to indicate mathematical division. However, this usage, though widespread in Anglophone countries, is not universal, and the symbol's use for division is not recommended in the ISO 80000-2 standard for mathematical notation.[1]

In mathematics[edit]

Plus and minuses. The obelus—or division sign—used as a variant of the minus sign in an excerpt from an official Norwegian trading statement form called «Næringsoppgave 1» for the taxation year 2010.

The obelus, an historical glyph consisting of a horizontal line with (or without) one or more dots, was first used as a symbol for division in 1659 in the algebra book Teutsche Algebra by Johann Rahn. Some think that John Pell, who edited the book, may have been responsible for this use of the symbol. Other symbols for division include the slash or solidus /, the colon :, and the fraction bar (the horizontal bar in a vertical fraction). The ISO 80000-2 standard for mathematical notation recommends only the solidus / or "fraction bar" for division, or the "colon" : for ratios; it says that the ÷ sign "should not be used" for division.[1]

In Italy and Russia, the ÷ sign is sometimes used to denote a range of values, in engineering contexts.[2]

Historically, an oblique form of the obelus, ('Commercial minus sign'), has also been used to represent subtraction in Northern Europe; such usage continued in some parts of Europe (including Norway and, until fairly recently, Denmark).[3]

In computer systems[edit]

The symbol was assigned to code point 0xF7 in ISO 8859-1, as the "division sign" and has the code point U+00F7.[4] In HTML, it can be encoded as ÷ or ÷ (at HTML level 3.2), or as ÷.

Keyboard entry[edit]

In Microsoft Windows, this division sign is produced with Alt+0247 (or 246 with no zero) on the number pad, or by pressing Alt Gr+⇧ Shift++ when an appropriate keyboard layout is in use. In classic Mac OS and macOS, it is produced with ⌥ Option+/.

On UNIX-based systems using Screen or X with a Compose key enabled, it can be produced by composing : (colon) and - (hyphen/minus). It may also be input using its Unicode code-point (F7) by pressing Control+⇧ Shift+u f7space.

In LaTeX, the division sign is obtained by \div.

In Chrome OS (with International/Extended keyboard setting) AltGr+⇧ Shift+>. Otherwise, the Unix-style methods may be used.

See also[edit]

Notes[edit]

  1. ^ a b ISO 80000-2, Section 9 "Operations", 2-9.6
  2. ^ "6. Writing Systems and Punctuation". The Unicode® Standard: Version 10.0 – Core Specification (PDF). Unicode Consortium. June 2017. p. 280, Obelus.
  3. ^ Cajori, Florian (1993), A history of mathematical notations (two volumes bound as one), Dover, pp. 242, 270–271, ISBN 9780486677668. Reprint of 1928 edition.
  4. ^ Korpela, Jukka (2006), Unicode Explained: Internationalize documents, programs, and web sites, O'Reilly Media, Inc., p. 397, ISBN 9780596101213

External links[edit]

The dictionary definition of division sign at Wiktionary