Purplemath contains practical algebra lessons demonstrating useful techniques and pointing out common errors. Lessons are written with the struggling student in mind, and stress the practicalites over the technicalities. Links and other resources also available.

A complete course in arithmetic. Book I of Euclid's Elements. A complete course is algebra. Topids in trigonometry. Topics in precalculus. An approach to calculus. The evolution of the eal numbers.

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