Guillaume de l'Hôpital

Guillaume François Antoine, Marquis de L'Hospital or L' Hôpital ( [ lopi'tal ] ) (* 1661 in Paris, † February 2, 1704 ) was a French mathematician. He is probably best known for the set named after him ( rule of L' Hospital), but was actually discovered by Johann Bernoulli.

Family

Hospital came from a respected noble family. His father Anne -Alexandre de l' Hospital ( Comte de Saint Mesme died 1701) was the royal lieutenant general and connected to the house Orleans ( Gaston d' Orleans). His mother was Elisabeth Gobelin, formerly maid of honor of the Grand Duchess of Tuscany and daughter of the State Council and State Secretary Claude Gobelin (died 1666).

Hospital married on January 10, 1688 Marie Charlotte de Romilly de la Chesnaye, and together they had one son and three daughters. From his marriage had the title of Comte d' Entremonts Hospital, next to his titles Marquis de L'Hospital, Marquis de Sainte Mesme et de Mantellier.

Life

Hospital was interested in early mathematics and showed mathematical talent ( he solved a problem with 15 years of Blaise Pascal on the cycloid, which came up in a conversation ), but initially chose a civil usual career as a cavalry officer. He gave the place on because of myopia, but especially to operate mathematical studies. In Paris he belonged in 1690 to the circle of the philosopher and mathematician Nicolas Malebranche. There he met Johann Bernoulli, when he visited Paris in 1691 and made known the newly developed by Leibniz calculus. He has lectured for the circle to Malebranche and then took the hospital with him private lessons when he invited him to his castle in 1692 Oucques (Canton Marchenoir ). They were then in correspondence. He paid him even that he provided him new results exclusively.

Hospital is also the author of the first textbook on differential calculus, which was released in 1696. It includes his teacher Johann Bernoulli writings. In a foreword Hospital proves the Bernoulli and Leibniz his thanks, but takes the same time lay claim to have developed the fundamentals of presentation of the differential calculus in his book itself. His textbook was very influential and experienced editions until, 1781. Was commented on, among others, Pierre de Varignon. Johann Bernoulli himself arose only after the death of Hospital claims, large parts of the book itself to have written. Only in the 20th century, the manuscripts of Bernoulli's lectures in Paris, where Hospital followed in his book, and his financial arrangements with hospital were known.

Because of his noble stand he could not join readily the Academie des Sciences, but received at their reorganization in 1699, a position of honor (Vice President). He corresponded with, among others, Leibniz and Christian Huygens, he introduced her to the new calculus.

At his death he left the manuscript to another book ( Traité Analytique of sections coniques et de leur usage pour la résolution of équations dans les problèmes tant déterminés qu'indéterminés ), this time on integral calculus, which appeared in 1707 and second edition 1720. Plans to publish the book in his lifetime he had given up after he was one of a plan of Leibniz to publish a book about himself.

Writings

• Analysis of infiniment petits pour l' intelligence of lignes courbes, 1696th 2nd edition 1715
• Traité Analytique of sections coniques et de leur usage pour la resolution of équations dans les problemes tant détermines qu'indétermines, 1776.