Tricki, a repository of mathematical know-how
tricki.org
tricki.org
I think there's a pretty big fascination among mathematicians to collect and organize the universe of information. It's always fun to think of mapping dependencies between all known proofs
[1] https://gowers.wordpress.com/2010/09/24/is-the-tricki-dead/
That homepage isn't very informative, but you can search for any topic and find explanations and problems that can be solved from that. For example: radical axis [2]
If you're looking for a book, The Art and Craft of Problem Solving by Paul Zeitz is the most recommended.
[1] http://www.artofproblemsolving.com/wiki/index.php/Main_Page
[2] http://www.artofproblemsolving.com/wiki/index.php/Radical_ax...
Dumb question maybe, but is knowledge like this often used in symbolic solver software? If so, would it be useful to implement examples in a programming language like Gerald Sussman did in Structure and Interpretation of Classical Mechanics?
A lot of big solvers use algorithms[0] that can't always be reduced into a reasonable series of steps for producing nice step-by-step output, which is why e.g. Wolfram Alpha will occasionally manage to symbolically integrate something but tells you that a step-by-step solution is unavailable. (This happens even with plain algebra; Wolfram Alpha can explain how to derive the quadratic equation but not the cubic.)
Could you elaborate more on the nature of the examples from this book for those of us who haven't read it?
[0] Risch algorithm, Gaussian elimination, etc.