Budan_de_Boislaurent
# Ferdinand Francois Désiré Budan de Boislaurent

### Born: 28 Sept 1761
in Limonade, Cap-Francais, Saint-Domingue (now Haiti)

Died: 6 Oct 1840
in Paris, France

**Francois Budan** began his education at the age of eight at a College in Juilly. He showed a great liking for the sciences but, as these were not part of the standard teaching, he received special mathematical tuition two days per week.
Budan took up the study of medicine in Paris and received the title of doctor for a thesis entitled

Essai sur cette question d'économie médicale : Convient-il qu'un malade soit instruit de sa situation?

Budan is considered an amateur mathematician and he is best remembered for his discovery of a rule which gives necessary conditions for a polynomial equation to have n real roots between two given numbers. The rule was in a memoir sent to the Institute in 1803 but it was not made public until 1807. A paper giving a proof was presented to the Academy in 1811 and published in 1822.

Fourier had independently discovered a rule which he taught in a course from 1797 but Fourier's version was not published until 1831, after his death.

**References (4 books/articles)**

JOC/EFR December 1996