Descartes***

This book is really great! It reminds me of a friend of mine who has always been interested in mathematics but always felt that algebra and geometry were two separate fields. After reading this book, he had a deeper understanding of Descartes' analytic geometry and the connection between the two. I think this book is not only suitable for mathematics lovers, but also for people like my friend who want to understand mathematics more comprehensively. It is like a key that opens another door to the world of mathematics.