He had always been "good at math," but the standard school textbooks felt like cookbooks—follow the recipe, get the result, forget it by Friday. Rusczyk’s book was different. On the very first page, the author didn't just give a formula; he asked a question. He invited the reader to play, to fail, and then to discover.
The book is (PDF pagination matches print), split into 22 chapters plus appendices. Here’s how it builds deep understanding: introduction to algebra by richard rusczyk pdf