Open-source textbooks are popular today especially among students who need to be more practical due to budget constraints. College students who need resource materials in math can check out any of the following books available online for free.

Open-source textbooks are gaining popularity these days. Many students are given the freedom to choose the books they would use when taking college courses. The idea is to enable them to find more practical yet effective resource materials. To date, there are numerous open source books available for free in online and/or PDF versions. Here are 10 of the most recommended for college mathematics courses.

• Abstract Algebra: Theory and Applications by Tom Judson. The textbook teaches abstract algebra principles and theory specifically to college students in their junior and senior years. The strengths include a broad range of exercises (computational and theoretical) with nontrivial applications.
• Fundamentals of Mathematics by Denny Burzynski and Wade Ellis. As a work text, this book covers traditional topics in modern pre-algebra courses. It also tackles other important topics like elementary analytic geometry, estimation, and introductory algebra.
• A Gentle Introduction to the Art of Mathematics by Joseph Fields. This is one of the most popular free open-source math textbooks for obvious reasons. The content focuses on foundations of the subject and introduces students to many important techniques about mathematical proof. Amusing quotations are provided at the start of every chapter.
• A First Course in Linear Algebra. The introductory textbook is designed specifically for college sophomores and juniors. The content includes discussions about systems of linear equations. From there, other concepts are covered like matrix algebra.
• Analysis 1 by Jairus M. Khalagai. The material is divided into three units. The first consists of analysis on real line; the second is about vector analysis; and the third covers complex analysis. The book is written based on the fact that mathematics is about analysis.
• Calculus by Ralph W.P. Masenge. The four-unit module covers everything students should learn about calculus. The first two parts cover basic concepts of integral and differential calculus. The third unit is about sequences of numbers and infinite series. The last is about integral and differential calculus of functions of variables.
• Understanding Algebra by James W. Brennan. The book is highly recommended to college students who need a refresher about algebra. This is for those who are preparing for more complex college-level mathematics and who are into homeschooling.
• Probability and Statistics by Paul Chege. Students who are studying statistics will find this book most helpful. The three units consist of descriptive statistics, random variables, and probability theory.
• Numerical Methods with Applications by Autar K. Kaw. Like many open-source math textbooks, this one is designed to integrate math concepts with practical applications. There are chapters about approximation and errors, differentiation, nonlinear equations, interpolations, and more.
• A Modern Formal Logic Primer by Paul Teller. The book has associated solutions manual to serve as guide for students when solving given mathematical exercises. This textbook was originally published by Prentice Hall in 1989 but was pulled out when Pearson Education bought the company. The author was given the right to publish it on his own and so he did but as an open-source material.

Image by claudiadaggett