Robert Recorde

Robert Recorde (ca. 1512–1558) var en walisisk fysiker og matematiker. Han oppfant likhetstegnet (=).

Publikasjoner

Recorde publiserte en rekke arbeider innen feltene matematikk og medisin, hovedsakelig i formen av den dialog mellom professor og student, slik som:
 The Grounde of Artes, teachings the Worke and Practise, of Arithmeticke, both in whole numbers and fractions (1543), den første engelske algebrabok.
 The Pathway to Knowledge, containing the First Principles of Geometry ... bothe for the use of Instrumentes Geometricall and Astronomicall, and also for Projection of Plattes (London, 1551)
 The Castle of Knowledge, containing the Explication of the Sphere both Celestiall and Materiall, etc. (London, 1556) En bok som forklarer Ptolemasik astronomi mens den kopernikanske heliosentrike modellen nevnet i forbifarten. 
 The Whetstone of Witte, whiche is the seconde parte of Arithmeteke: containing the extraction of rootes; the cossike practise, with the rule of equation; and the workes of Surde Nombers (London, 1557). Dette er boken som introduserte likhetstegnet. Som et resultat av utgivelsen av denne boken er Recorde blitt kreditert for å ha introdusert algebra i England.
 et medisinsk arbeide, The Urinal of Physick (1548), ofte gjengitt.<ref name="The Urinal of Physick">[http://books.google.ca/books/about/The_urinal_of_physick.html?id=Sax491XagIgC&redir_esc=y The Urinal of Physick], av Robert Recorde, 1548; hos Google Books</ref>

Sherburne sier at Recorde også utgav Cosmographiae isagoge, og at han skrev bøker ved navn De Arte faciendi Horologium og De Usu Globorum et de Statu temporum. Recordes hovedbidrag til utviklingen av algebra var måten å systematisere dens notasjon.

 Se også 
 Likhetstegn
 Ligning (matematikk)

 Referanser 


Robert Recorde, The Whetstone of Witte (London, England:  John Kyngstone, 1557), s. 236 (although the pages of this book are not numbered).  From the chapter titled "The rule of equation, commonly called Algebers Rule" (p. 236):  "Howbeit, for easie alteration of equations.  I will propounde a fewe examples, bicause the extraction of their rootes, maie the more aptly bee wroughte.  And to avoide the tediouse repetition of these woordes:  is equalle to:  I will sette as I doe often in worke use, a paire of paralleles, or Gemowe [twin, from gemew, from the French gemeau (twin / twins), from the Latin gemellus (little twin)] lines of one lengthe, thus: = , bicause noe .2. thynges, can be moare equalle."  (However, for easy manipulation of equations, I will present a few examples in order that the extraction of roots may be more readily done.  And to avoid the tedious repetition of these words "is equal to", I will substitute, as I often do when working, a pair of parallels or twin lines of the same length, thus: = , because no two things can be more equal.)

 Eksterne lenker 

St. Andrew's University Maths History biography
Robert Recorde and other Welsh Mathematicians
100 Welsh Heroes –  Robert Recorde
Earliest Uses of Symbols of Relation
Earliest Known Uses of Some of the Words of Mathematics This contains numerous quotations from Recorde.
RECORDE (Robert) in Charles Hutton's Mathematical and Philosophical Dictionary''
Robert Recorde's life and works on h2g2
Current publisher of Robert Recorde's books in the form of original reproductions 


Kategori:Britiske matematikere
Kategori:Engelske fysikere
Kategori:Engelske leger
Kategori:Britiske filosofer
Kategori:Dødsfall i 1558