# Best book for an engineer to refresh everything and study math for fun?

I like Calculus, Linear Algebra, Number Theory, Geometry, etc. I pretty much like everything about Math. :) The good thing about math is that all you need is a good book, a stack of paper, a pencil and you are good to go! Is there a fun undergraduate textbook you can recommend me to refresh everything? THX!

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I won't make any specific suggestions, but one way to go without breaking the bank is to purchase Dover books in any subject area you're interested in (the average cost I've seen is around \$10.00 as opposed to \$100.00). –  Clayton Jan 20 '13 at 20:31
What is Mathematics? An Elementary Approach to Ideas and Methods, Courant and Robbins, Oxford university Press. –  David Mitra Jan 20 '13 at 20:33
For each topic, there are numerous books to look at. Also, it would be more helpful if you can specify what you like. Do you like working through numerous examples? Seeing the proofs? Working on problems? –  Calvin Lin Jan 20 '13 at 20:35
I like to solve problems and check the answers after... –  chrisapotek Jan 20 '13 at 20:37
+1 to what @Clayton had to say. And/or check something out from the library, grab a used copy. If you are starting from scratch, Zill's Advanced Engineering Mathematics takes you from calculus to vector calculus to differential equations to complex analysis. –  JohnD Jan 20 '13 at 20:38