‎"LAGRANGE, (LA GRANGE), JOSEPH LOUIS. - A BREAKTHROUGH IN ""THE THEORY OF EQUATIONS"".‎
‎Sur la Résolution des Équations Numériques. (On the Solution of numerical Equations).‎

‎(Berlin, Haude et Spener, 1769). 4to. Without wrappers as issued in ""Mémoires de l'Academie Royale des Sciences et Belles-Lettres"", Année 1767, Tome XXXIII, pp. 311-352.‎

Reference : 46556

‎First edition of a monumental paper in the theory of equations by ""one of the greatest mathematicians of all times"" (Cajori). In this memoir, which deals with the solutiuon of numerical equations, Lagrange examines the roots of algebraic equations and provides methods of separating the real and imaginary roots and of approximating the real roots with continued fractions.Parkinson ""Breakthroughs"" 1767 P.‎