Andreescu Titu, Enescu Bogdan. Mathematical Olympiad Treasures

Birkhauser Boston, 2003. — 234 p.Mathematical Olympiad Treasures contains a stimulating collection of problems in geometry and trigonometry, algebra, number theory, and combinatorics. It encourages readers to think creatively about techniques and strategies for problem solving in the real world.The problems are clustered by topic into self-contained chapters. The book begins with elementary facts, followed by carefully selected problems and detailed, step-by-step solutions, which then lead to more complicated, challenging problems and their solutions. Reflecting the experience of two professors and coaches of Mathematical Olympiads, the text will be valuable to teachers, students, and puzzle enthusiasts.