Gabriel Cramer

Gabriel Cramer (July 31, 1704 - January 4, 1752) was a Swiss mathematician born in Geneva.

He showed great precocity in mathematics and already at 18 he received his doctorate and at 20 he was an adjunct professor of mathematics. He professor of mathematics at the University of Geneva during the period 1724-27. In 1750 he held the chair of philosophy at the said university. In 1731 he presented before the Paris Academy of Sciences, a report on the multiple causes of the inclination of the orbits of the planets.He had a son named Felipe Cramer Montilla.

Postula of the book Introduction to l’analyse de lignes courbes algébriques

He edited the works of Johann Bernoulli (1742) and Jacques Bernoulli (1744) and Leibniz's Comercium epistolarum. His fundamental work was the Introduction à l'analyse des courbes algébriques (1750), in which he developed the theory of algebraic curves according to Newtonian principles, demonstrating that a curve of degree n is given by N points located on it, where N is given by the expression:

${displaystyle N={frac {n(n+3)}{2}}}}}$

Cramer's Rule is a theorem in linear algebra, which gives the solution of a linear system of equations in terms of determinants. It is named after Gabriel Cramer (1704 - 1752), who published the rule in his 1750 Introduction à l'analyse des lignes courbes algébriques, although Colin Maclaurin also published the method in his Treatise of Geometry of 1748 (and probably knew of the method as early as 1729).

Some posts

• Quelle is the cause of the figure elliptique des planètes et de la mobilité de leur aphélies?Genf 1730.
  Work presented to the Parisian Academy. He got the 2nd prize. 1.♪ award to Johann Bernoulli
• Introduction a l′analyse de lignes courbes algébriquesGenf 1750
• Opera Omnia (full works) von Johann Bernoulli, 1742, 4 tomos
• Works of Jakob I. Bernoulli, 1744, 2 volumes.
  include all production of Jakob Bernoulli, less Ars conjectandi
• The publication (together with Johann Castillon) of correspondence between Johann Bernoulli and Leibniz, 1745