An inexpensive, open-source alternative to the traditional Calculus textbook.
Coming Soon: Version 4.0, containing a new chapter on Vector Calculus and updates to the 3.0 content. (Planned release date: Spring, 2018)
APEX Calculus is a calculus textbook written for traditional college/university calculus courses. It has the look and feel of the calculus book you likely use right now (Stewart, Thomas & Finney, etc.). The explanations of new concepts is clear, written for someone who does not yet know calculus. Each section ends with an exercise set with ample problems to practice & test skills (odd answers are in the back).
APEX Calculus looks like a "regular" calculus book in most all respects except the price. Anyone can download the .pdf version of the text for free. Want a print copy? Feel free to print it yourself, or buy a b&w copy from Amazon.com for $15.
While APEX Calculus looks like an inexpensive version of the traditional calculus text, a closer look will show it's a better calculus book for an even better price. Check out the comparison section for more details.