Books like Understanding Maths by Graham Lawler

An encyclopedic reference edited by Fields Medalist Timothy Gowers, the Princeton Companion to Mathematics offers nearly 200 essays by leading mathematicians, covering key concepts, historical development, and interdisciplinary impact of modern mathematics.

This is a text in basic mathematics with multiple uses for either high school or college level courses. Readers will get a firm foundation in basic principles of mathematics which are necessary to know in order to go ahead in calculus, linear algebra or other topics. The subject matter is clearly covered and the author develops concepts so the reader can see how one subject matter can relate and grow into another.

This is the perfect introduction for those who have a lingering fear of math. If you think that math is difficult, confusing, dull or just plain scary, then The Math Handbook is your ideal companion. Covering all the basics including fractions, equations, primes, squares and square roots, geometry and fractals, Dr. Richard Elwes will lead you gently towards a greater understanding of this fascinating subject. Even apparently daunting concepts are explained simply, with the assistance of useful diagrams, and with a refreshing lack of jargon. So whether you're an adult or a student, whether you like Sudoku but hate doing sums, or whether you've always been daunted by numbers at work, school or in everyday life, you won't find a better way of overcoming your nervousness about numbers and learning to enjoy making the most of mathematics

An engaging exploration of mathematical ideas for general readers.