Florimond de Beaune (7 October 1601,

Blois Blois ( ; ) is a commune and the capital city of Loir-et-Cher department, in Centre-Val de Loire, France, on the banks of the lower Loire river between Orléans and Tours. With 45,898 inhabitants by 2019, Blois is the most populated city of the ...

– 18 August 1652, Blois) was a French jurist and

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

, and an early follower of

René Descartes René Descartes ( or ; ; Latinized: Renatus Cartesius; 31 March 1596 – 11 February 1650) was a French philosopher, scientist, and mathematician, widely considered a seminal figure in the emergence of modern philosophy and science. Ma ...

.. The material on de Beaune is o
p. 187
R. Taton calls him "a typical example of the erudite amateurs" active in 17th-century science. In a 1638 letter to Descartes, de Beaune posed the problem of solving the

differential equation In mathematics, a differential equation is an equation that relates one or more unknown functions and their derivatives. In applications, the functions generally represent physical quantities, the derivatives represent their rates of change, an ...

\frac=\frac

now seen as the first example of the inverse tangent method of deducing properties of a curve from its

tangent In geometry, the tangent line (or simply tangent) to a plane curve at a given point is the straight line that "just touches" the curve at that point. Leibniz defined it as the line through a pair of infinitely close points on the curve. Mo ...

s. His ''Tractatus de limitibus aequationum'' was reprinted in England in 1807; in it, he finds

upper and lower bounds In mathematics, particularly in order theory, an upper bound or majorant of a subset of some preordered set is an element of that is greater than or equal to every element of . Dually, a lower bound or minorant of is defined to be an eleme ...

for the solutions to

quadratic equation In algebra, a quadratic equation () is any equation that can be rearranged in standard form as ax^2 + bx + c = 0\,, where represents an unknown value, and , , and represent known numbers, where . (If and then the equation is linear, not q ...

s and

cubic equation In algebra, a cubic equation in one variable is an equation of the form :ax^3+bx^2+cx+d=0 in which is nonzero. The solutions of this equation are called roots of the cubic function defined by the left-hand side of the equation. If all of th ...

s, as simple functions of the coefficients of these equations. His ''Doctrine de l'angle solide'' and ''Inventaire de sa bibliothèque'' were also reprinted, in Paris in 1975.. Another of his writings was ''Notae breves'', the introduction to a 1649 edition of Descartes' '' La Géométrie''..

References

Further reading