Division sign
The division sign (÷) is a mathematical symbol consisting of a short horizontal line with a dot above and another dot below, used in Anglophone countries to indicate the operation of division. This usage, though widespread in some countries, is not universal and the symbol has a different meaning in other countries. Its use to denote division is not recommended in the ISO 80000-2 standard for mathematical notation.[1] In mathematics The obelus, a 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, although previous writers had used the same symbol for subtraction.[2] Some near-contemporaries believed that John Pell, who edited the book, may have been responsible for this use of the symbol.[2] Other symbols for division include the slash or solidus /, the colon :, and the fraction bar (the horizontal bar in a vertical fraction).[3][4] 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, Poland and Russia, the ÷ sign was sometimes used to denote a range of values, and in Scandinavian countries it was, and sometimes still is, used as a negation sign:[5] the Unicode Consortium has allocated a separate code point, U+2052 ⁒ COMMERCIAL MINUS SIGN for this usage uniquely;[6][7] the exact form of the symbol displayed is typeface (font) dependent. In computer systemsEncodingThe symbol was assigned to code point 0xF7 in ISO 8859-1, as the "division sign". This encoding was transferred to Unicode as U+00F7.[8] In HTML, it can be encoded as Unicode provides various division symbols:[9]
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