Math Books

The Golden Ratio is a well written book, and a great coverage of mathematical ideas of importance to computer scientists. The fixed point in calculus is the exponential of e. This number is at the center of one of the most import concepts of our age. Find out why in this book. Euler is one of the greats of all time, and his famous formula is key to many ideas in engineering, math, and physics.
While not on a single subject like many of the other books in my list, this is truly a fun book (at least to me). It covers five great theories of math in the last century, all of which are used in computer science and engineering (two even directly from it). Definitely worth the read. The square root of negative one is commonly used, here you will see where it came from and why it is unavoidable. Zero is another key area of mathematics that was denied for ages, but it is half of computer science.
Who can resist a book on the history of algebra? (not me) While on the subject of algebra, I have to list a book that includes some of my writing. I answered questions for Dr. Math (an online service) for years, and some of my answers actually were judged worthy for the book. It is really aimed for jr-high level, but perhaps you know someone... I love math from around the world. There are subtle differences in approach which can be used to strengthen your logic. This is probably the most rigorous book on ethnomathematics.
This is probably the best book on how to solve problems you will ever find. It is a classic.

Already read those? I generally suggest reading popular math or physics books.

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