Florimond de Beaune

Florimond de Beaune, who lived from 1601 to 1652, was a French jurist and mathematician, born and died in Blois, and an early follower of Rene Descartes. The historian Rene Taton calls him a typical example of the erudite amateurs active in seventeenth century science. In a letter to Descartes in 1638 he posed a problem that can be restated as solving the differential equation dy/dx = (y minus x) over a constant, now seen as the first example of the inverse tangent method of deducing properties of a curve from its tangents. His Tractatus de limitibus aequationum, reprinted in England in 1807, finds upper and lower bounds for the solutions of quadratic and cubic equations as simple functions of their coefficients. He also wrote the Notae breves, the introduction to the 1649 edition of Descartes's La Geometrie, and his Doctrine de l'angle solide and the inventory of his library were reprinted in Paris in 1975.