Teaching yourself mathematics from home is difficult. In as much as it is an intellectual journey, it is also emotional. Many people begin this journey but drop along the way. Mathematics is a subject that you may wish to study further. People consider this path to be tortuous with long hours and low pay. A more pragmatic way of doing mathematics is by finding the time and learning it every day. In this way, you will reconnect with it more as you know new things on a daily.
Why Should you Learn Mathematics?
If you still love solving problems and puzzling, then we can conclude that you love mathematics. These activities are suitable as they will give you a dopamine hit. In learning this subject, you slowly come from saying Mathematics is hard to it becoming easy. As you continue learning, you climb up the ladder to solving more complex problems. It rewards when you have patience, creativity, and persistence in learning it. Happiness is when you break down the impossible problems making them possible. It is profoundly enriching and satisfying, making the impossible possible due to ingenuity and hard work.
You should know that the mathematics you will get exposed to at the university level differs from what you learned in high school—the focus shifts from revolving on rote composition to reasoning, deduction, and logic.
Right Book and Courses to Use
As you grow into a great self-learner, it is vital to pick exercises and solutions books. After some time, you can change to using books without explanations and exercises. In the beginning stage, you require feedback so that you can learn from your mistakes. By following this tip, you will move forward any time you get stuck.
The books that you might pick might vary from those you could have been using at the University. Lean towards books that have better motivation, exposition, and examples. It would be helpful if you did not go for the kindle version of the books but stick to the print since a few of the kindle books may contain display and formatting errors resulting from the conversion to digital format. As a result, you will notice that the mistakes contribute to the bad review of some best books on Amazon.
Foundations
Assuming that high school is the last level of your mathematics, here are the books that can help you.
The Art Of Problem Solving: It is a good starter book. You start with Volume 1, then go to Volume 2.
Mathematics for Nonmathematician: It has a handful of light exercises. It is suitable for leisure read and has a historical view.
Concepts of Modern Mathematics: Unlike the Mathematics for Nonmathematicians, this book will provide a modern perspective. The book does not have exercises, but it will motivate you to read other related books.
Book of Proof: Just like the name suggests, it is a pretty little proofs book. It is not lengthy and has enough exercises. It has a gentle way of taking you through an introduction to proofs.
All in all, you should do regular exercise, take breaks from studying and all will be good. Alternate between more accessible and complex books. All the best in your learning!