The book "57th Moscow Mathematical Olympiad", written by authors Dorichenko S. A. and Yaschenko and . In. is a fascinating and deep immersion into the world of mathematical problems that were offered to the participants of the famous Moscow mathematical tournament. This publication not only attracts the attention of lovers of mathematics, but also is a real storehouse of knowledge for students, teachers and anyone who seeks to develop their analytical abilities and logical thinking. This book contains the tasks that were presented at the 57th Moscow Mathematical Olympiad, held in 2021. The authors, possessing rich experience in the field of teaching and organization of Olympiads, offer readers not just a set of tasks, but a whole methodological system that will help to understand more deeply not only the mathematics itself, but also approaches to solving complex problems. Each task is accompanied by a detailed analysis, which makes the book especially useful for those who are preparing for the Olympics or want to improve their mathematical knowledge. Who can like this edition? First of all, it will be interesting for high school students and students seeking to participate in olympiads and competitions, as well as teachers who are looking for quality materials for the preparation of their students . But not only them: the book will attract the attention of all who like to solve puzzles and strive to develop their intellectual abilities. Even if you do not plan to participate in the Olympics, the tasks in this book can be a great way to spend time usefully, developing logical thinking and creativity. The topics raised in the book are diverse and cover a wide range of mathematical disciplines: from algebra and geometry to combinatorics and number theory. Each task is not just a mathematical puzzle, but a challenge that requires a non-standard approach and a deep understanding of the subject. The authors skillfully combine theory and practice, which makes each page of the book not only informative, but also fascinating. The style of Dorichenko and Yashchenko is distinguished by clarity and accessibility. They are able to explain complex things in simple language, which makes their books popular with a wide audience. Both authors have a lot of publications and experience in the field of education, which allows them to create high-quality and in-demand materials. Their previous works, such as Mathematics for Olympiads and Problems in Mathematics for High School Students, have also won the recognition and love of readers. The book “57th Moscow Mathematical Olympiad” is not just a collection of problems, but a whole world of mathematical discoveries that awaits its researchers. It will be an excellent assistant for everyone who wants not only to prepare for the Olympics, but also just enjoy the process of solving interesting problems. If you are looking for a way to develop your mathematical skills, improve logical thinking or just want to spend time usefully, this publication will become your reliable companion. Do not miss the opportunity to discover the world of mathematics with the help of the “57th Moscow Mathematical Olympiad” a book that inspires, teaches and gives joy to solve problems!