Robert Recorde
Oddi ar Wicipedia
Mathemategydd a ffisegydd o Gymro oedd Robert Recorde (tua 1510 – 1558). Ef oedd y cyntaf i ddefnyddio'r hafalnod '=' ym 1557. Fe'i ganwyd i deulu parchus yn Ninbych-y-Pysgod, Sir Benfro, ac fe aeth ymlaen i astudio ym mhrifysgolion Rhydychen a Chaergrawnt. Fe fu farw yng ngharchar yn Southwark, wedi iddo fynd i ddyled.
[golygu] Llyfrau
- The Grounde of Artes, teachings the Worke and Practise, of Arithmeticke, both in whole numbers and fractions (c. 1540)
- 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 (Llundain, 1551)
- The Castle of Knowledge, containing the Explication of the Sphere both Celestiall and Materiall, etc. (Llundain, 1556)
- The Whetstone of Witte, which is the second part of Arithmetike, containing the Extraction of Rootes, the Cossike Practice, with the Rules of Equation, and the Woorkes of Surde Numbers. (Llundain, 1557). Dymar'r llyfr a gyflwynodd yr hafalnod a'r llyfr Saesneg cyntaf ar algebra.
- The Urinal of Physic (1548).