German mathematician and astronomer, born in Königsberg (= king's mountain, in Latin Regiomontanus) who, beyond of establishing the study of algebra and geometry in Germany, he reactivated the study of astronomy in Renaissance. He studied at the universities of Leipzig and Vienna where he studied mathematics and astronomy.
In Rome he studied Greek and philosophy and went on to translate ancient scientific books. Back in Germany he created a printing company and an observatory in Nuremberg, in order to stimulate science and literature. Returning to Rome at the invitation of Pope Sixtus IV, he died suddenly, apparently dead from poisoning, as he was a vehement critic of certain currents of ecclesiastical thought.
An eminent mathematician, perhaps the most influential of the fifteenth century, he began to publish De triangulis omnimodis (1464), a remarkable treatise on trigonometry that marked the rebirth of this branch of mathematics in Europe, which would only be definitively printed in the following decade (1533). In Tabulae directionum (1490), he emphasized the tangent function, a subject dealt with poorly in the previous work. In Epitome of Almagest he emphasized the mathematical parts of Ptolemy's memorable work.
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http://www-history.mcs.st-andrews.ac.uk/
Source: http://www.dec.ufcg.edu.br/biografias/
Order R - Biography - Brazil School
Source: Brazil School - https://brasilescola.uol.com.br/biografia/regiomontanus.htm