Viète, François

Viète or Vieta, François

(fräNswä` vyĕt, vyātä`, vīē`tə), 1540–1603, French mathematician. As a founder of modern algebra, he introduced the use of letters as algebraic symbols and correlated algebra with geometry and trigonometry. A prominent lawyer, he was attached for a time to the parliament of Brittany and served as privy councillor to Henry IV, for whom he decoded messages sent by Philip II of Spain to his soldiers in the Netherlands.