Johann Rahn
Johann Rahn (Latinised form Rhonius) (10 March 1622 – 25 May 1676) was a Swiss mathematician who is credited with the first use of the division sign, ÷ (a repurposed obelus variant) and the therefore sign, ∴. The symbols were used in ''Teutsche Algebra'', published in 1659. John Pell collaborated with Rahn in this book, which contains an example of the Pell equation. It is uncertain whether Rahn or Pell was responsible for introducing the symbols. Books Teutsche Algebra- Johann H. Rahn Literature *R. Acampora ''Johann Heinrich Rahn und seine Teutsche Algebra'', in R. Gebhardt (Herausgeber) ''Visier- und Rechenbücher der frühen Neuzeit'', Schriften des Adam-Ries-Bundes Annaberg-Buchholz 19, 2008, S. 163–178 * Moritz Cantor: Rahn, Johann Heinrich . In: General German Biography (ADB). Volume 27, Duncker & Humblot, Leipzig, 1888, pp. 174 f *Noel Malcolm, Jacqueline Stedall ''John Pell (1611–1685) and His Correspondence with Sir Charles Cavendish: The Mental ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Johann Heinrich Rahn 1656
Johann, typically a male given name, is the German form of ''Iohannes'', which is the Latin form of the Greek name ''Iōánnēs'' (), itself derived from Hebrew name ''Yochanan'' () in turn from its extended form (), meaning "Yahweh is Gracious" or "Yahweh is Merciful". Its English language equivalent is John. It is uncommon as a surname. People People with the name Johann include: Mononym *Johann, Count of Cleves (died 1368), nobleman of the Holy Roman Empire *Johann, Count of Leiningen-Dagsburg-Falkenburg (1662–1698), German nobleman *Johann, Prince of Hohenzollern-Sigmaringen (1578–1638), German nobleman A–K * Johann Adam Hiller (1728–1804), German composer * Johann Adam Reincken (1643–1722), Dutch/German organist * Johann Adam Remele (died 1740), German court painter * Johann Adolf I, Duke of Saxe-Weissenfels (1649–1697) * Johann Adolph Hasse (1699-1783), German Composer * Johann Altfuldisch (1911—1947), German Nazi SS concentration camp officer executed for wa ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History One of the earliest known mathematicians were Thales of Miletus (c. 624–c.546 BC); he has been hailed as the first true mathematician and the first known individual to whom a mathematical discovery has been attributed. He is credited with the first use of deductive reasoning applied to geometry, by deriving four corollaries to Thales' Theorem. The number of known mathematicians grew when Pythagoras of Samos (c. 582–c. 507 BC) established the Pythagorean School, whose doctrine it was that mathematics ruled the universe and whose motto was "All is number". It was the Pythagoreans who coined the term "mathematics", and with whom the study of mathematics for its own sake begins. The first woman mathematician recorded by history was Hypati ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Division Sign
The division sign () is a symbol consisting of a short horizontal line with a dot above and another dot below, used in Anglophone countries to indicate mathematical division. However, this usage, though widespread in some countries, is not universal; it is used for other purposes in other countries and its use to denote division is not recommended in the ISO 80000-2 standard for mathematical notation. 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 ' by Johann Rahn, although previous writers had used the same symbol for subtraction. pp 270,271 Some near-contemporaries believed 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 mathemat ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Obelus
An obelus (plural: obeluses or obeli) is a term in typography that refers to a historical mark which has resolved to three modern meanings: * Division sign * Dagger * Commercial minus sign (limited geographical area of use) The word "obelus" comes from (obelós), the Ancient Greek word for a sharpened stick, spit, or pointed pillar. This is the same root as that of the word 'obelisk'. In mathematics, the first symbol is mainly used in Anglophone countries to represent the mathematical operation of division. In editing texts, the second symbol, also called a dagger mark , is used to indicate erroneous or dubious content; or as a reference mark or footnote indicator. It also has other uses in a variety of specialist contexts. Use in text annotation The modern dagger symbol originated from a variant of the obelus, originally depicted by a plain line , or a line with one or two dots . It represented an iron roasting spit, a dart, or the sharp end of a javelin, symbolizin ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Therefore Sign
In logical argument and mathematical proof, the therefore sign, , is generally used before a logical consequence, such as the conclusion of a syllogism. The symbol consists of three dots placed in an upright triangle and is read ''therefore''. While it is not generally used in formal writing, it is used in mathematics and shorthand. History According to Cajori, ''A History of Mathematical Notations,'' Johann Rahn used both the ''therefore'' and ''because'' signs to mean "therefore"; in the German edition of ''Teutsche Algebra'' (1659) the ''therefore'' sign was prevalent with the modern meaning, but in the 1668 English edition Rahn used the ''because'' sign more often to mean "therefore". Other authors in the 18th century also used three dots in a triangle shape to signify "therefore", but as with Rahn, there wasn't much in the way of consistency as to how the triangle was oriented; ''because'' with its current meaning appears to have originated in the 19th century. In the 20th ce ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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John Pell (mathematician)
John Pell (1 March 1611 – 12 December 1685) was an English mathematician and political agent abroad. Early life He was born at Southwick in Sussex. His father, also named John Pell, was from Southwick, and his mother was Mary Holland, from Halden in Kent. The second of two sons, Pell's older brother was Thomas Pell. By the time he was six, they were orphans, their father dying in 1616 and their mother the following year. John Pell the elder had a fine library, which proved valuable to the young Pell as he grew up. He was educated at Steyning Grammar School and entered Trinity College, Cambridge, at the age of 13. During his university career he became an accomplished linguist; even before taking a B.A. degree in 1629, he corresponded with Henry Briggs and other mathematicians. He was promoted by seniority to M.A. in 1630 and taught in the short-lived Chichester Academy set up by Samuel Hartlib. On 3 July 1632 he married Ithamaria Reginald (also rendered as Ithamara or Ithuma ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pell Equation
Pell's equation, also called the Pell–Fermat equation, is any Diophantine equation of the form x^2 - ny^2 = 1, where ''n'' is a given positive nonsquare integer, and integer solutions are sought for ''x'' and ''y''. In Cartesian coordinates, the equation is represented by a hyperbola; solutions occur wherever the curve passes through a point whose ''x'' and ''y'' coordinates are both integers, such as the trivial solution with ''x'' = 1 and ''y'' = 0. Joseph Louis Lagrange proved that, as long as ''n'' is not a perfect square, Pell's equation has infinitely many distinct integer solutions. These solutions may be used to accurately approximate the square root of ''n'' by rational numbers of the form ''x''/''y''. This equation was first studied extensively in India starting with Brahmagupta, who found an integer solution to 92x^2 + 1 = y^2 in his ''Brāhmasphuṭasiddhānta'' circa 628. Bhaskara II in the 12th century and Narayana Pandit i ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Moritz Cantor
Moritz Benedikt Cantor (23 August 1829 – 10 April 1920) was a German historian of mathematics. Biography Cantor was born at Mannheim. He came from a Sephardi Jewish family that had emigrated to the Netherlands from Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ..., another branch of which had established itself in Russia. In his early youth, Moritz Cantor was not strong enough to go to school, and his parents decided to educate him at home. Later, however, he was admitted to an advanced class of the Gymnasium in Mannheim. From there he went to the University of Heidelberg in 1848, and soon after to the University of Göttingen, where he studied under Carl Friedrich Gauss, Gauss and Heinrich Martin Weber, Weber, and where Stern awakened in him a strong interest in histor ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Christoph Scriba
Christoph J. Scriba (6 October 1929 – 26 July 2013) was a German historian of mathematics. Life and work Scriba was born in Darmstadt and studied at ''Justus-Liebig-University Giessen''. He read James Gregory (mathematician), James Gregory's early writings on the calculus with Joseph Ehrenfried Hofmann, and was awarded his doctorate in 1957. Continuing with J.E. Hofmann, and with Bernard Sticker, he investigated the papers of John Wallis in Oxford in 1966, contributing to ''Studies on the Mathematics of John Wallis''. Scriba then taught at the University of Kentucky, the University of Massachusetts Amherst, University of Massachusetts and at the University of Toronto from 1959 to 1962. He became chairman of Technical University of Berlin's department of History of Mathematics in 1969. Then in 1975 he became Professor of History of Natural Science and Mathematics at the University of Hamburg and Director of the Institute until he retired in 1995. His successor there was Kari ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Jacqueline Stedall
Jacqueline Anne "Jackie" Stedall (4 August 1950 – 27 September 2014) was a British mathematics historian. She wrote nine books, and appeared on radio on BBC Radio 4's ''In Our Time'' programme. Early life Stedall was born in Romford, Essex, and attended Queen Mary's High School in Walsall. Her academic achievements included a BA in mathematics from Girton College, Cambridge, an MSc in statistics from the University of Kent, a PGCE from Bristol Polytechnic (now the University of the West of England), and a PhD in the history of mathematics from the Open University. Her PhD focused upon John Wallis' 1685 work ''Treatise of Algebra''. Career After her MSc degree, Stedall worked for three years as a statistician at the University of Bristol, and four years as an administrator for War on Want. Subsequently, she worked as a teacher for eight years. Stedall's academic career began in 2000, when she became a Clifford Norton student at The Queen's College, Oxford, studying the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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History Of Mathematical Notation
The history of mathematical notation includes the commencement, progress, and cultural diffusion of mathematical symbols and the conflict of the methods of notation confronted in a notation's move to popularity or inconspicuousness. Mathematical notation comprises the symbols used to write mathematical equations and formulas. Notation generally implies a set of well-defined representations of quantities and symbols operators. The history includes Hindu–Arabic numerals, letters from the Roman, Greek, Hebrew, and German alphabets, and a host of symbols invented by mathematicians over the past several centuries. The development of mathematical notation can be divided in stages. The "''rhetorical''" stage is where calculations are performed by words and no symbols are used. The "''syncopated''" stage is where frequently used operations and quantities are represented by symbolic syntactical abbreviations. From ancient times through the post-classical age,Or the Middle Ages. bursts o ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Florian Cajori
Florian Cajori (February 28, 1859 – August 14 or 15, 1930) was a Swiss-American historian of mathematics. Biography Florian Cajori was born in Zillis, Switzerland, as the son of Georg Cajori and Catherine Camenisch. He attended schools first in Zillis and later in Chur. In 1875, Florian Cajori emigrated to the United States at the age of sixteen, and attended the State Normal school in Whitewater, Wisconsin. After graduating in 1878, he taught in a country school, and then later began studying mathematics at University of Wisconsin–Madison. In 1883, Cajori received both his bachelor's and master's degrees from the University of Wisconsin–Madison, briefly attended Johns Hopkins University for 8 months in between degrees. He taught for a few years at Tulane University, before being appointed as professor of applied mathematics there in 1887. He was then driven north by tuberculosis. He founded the Colorado College Scientific Society and taught at Colorado College where ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |