Johannes Hudde

Johannes Hudde, also called Johannes van Waveren Hudde, was a Dutch mathematician, born on 23 April 1628 and dying on 15 April 1704, who was also burgomaster of Amsterdam from 1672 to 1703 and a governor of the Dutch East India Company. He studied law at Leiden but turned to mathematics under the influence of his teacher Frans van Schooten, working under him from 1654 to 1663. In his posthumous De reductione aequationum of 1713 he was the first to take literal coefficients in algebra as indifferently positive or negative. In van Schooten's Latin edition of Descartes's La Géométrie he published, with Johan de Witt and Hendrik van Heuraet, work of his own, an algorithm for finding a double root of a polynomial and two properties of polynomial roots known as Hudde's rules, which point toward algorithms of calculus. As burgomaster he had the canals flushed and promoted hygiene, and his marker stones for water levels were a basis for the NAP.