The material presented on this Web site is primarily suitable for high school and early college mathematics courses. It is divided into four massive sections that are devoted to basic arithmetic, trigonometry, precalculus, and an in-depth look at real numbers. Each section covers almost as many topics as a full course in the subject. The author clearly describes each concept and combines figures...

This online tutorial is intended for college students taking an early course in mathematical optimization or linear differential equations. Although it is written by a professor of economics, little economic theory is presented. This keeps the material centered on the mathematical aspects of optimization and differential equations, which have a wide range of scientific applications. The text is...

Xiao Gang of the University of Nice (France) maintains this site, which is highlighted by ten interactive mathematical exercises, including finding a polynomial with given values, decomposing a composed function, and finding the root of a function by successive tests. Selected exercises contain links to some of the ten online mathematical tools provided. Selected source code is provided. The site...