Analyse des Infiniment Petits pour l'Intelligence des Lignes Courbes

Analyse des Infiniment Petits pour l'Intelligence des Lignes Courbes (literal translation: Analysis of the infinitely small to understand curves), 1696, is the first textbook published on the infinitesimal calculus of Leibniz.

It was written by the French mathematician Guillaume de l'Hôpital, and treated only the subject of differential calculus.

The rule is believed to be the work of Johann Bernoulli, since l'Hôpital, a nobleman, paid Bernoulli a retainer of 300₣ per year to keep him updated on developments in calculus and to solve problems he had.

Moreover, the two signed a contract allowing l'Hôpital to use Bernoulli's discoveries in any way he wished.

Bernoulli, who was known for being extremely jealous, claimed to be the author of the entire work.