# Mathematical Treasure: Lacroix's Elements of Algebra

Author(s):
Frank J. Swetz (The Pennsylvania State University)

Silvestre Lacroix first wrote his Elements of Algebra for the Use of the Central School of Four Nations. This institution was established in Paris in 1795 as a result of the French Revolution. Five such schools were planned to better serve the common people; however, only three were actually founded. In 1802, the Central School was discontinued. The fourteenth edition of the Algebra, as shown here, was published in 1825.

This excerpt from the Contents (pages vj and vij) shows some of the topics presented in this “revised and corrected” edition.

On page 13 of the Algebra, Lacroix demonstrated the conversion of a problem into algebraic form.

Page 147 contains a discussion of rational and irrational numbers: $\sqrt{2}$ is noted as being “incommensurable or irrational.”

This material is obtained through the courtesy of the University of California Libraries. A complete digital copy can be read on the Internet Archive.

Index to Mathematical Treasures

Frank J. Swetz (The Pennsylvania State University), "Mathematical Treasure: Lacroix's Elements of Algebra," Convergence (February 2017)