Lectures on partial-derivative equations . Additional Chapters by Yuriy Vasilyevich Egorov is a fascinating and deep dive into the world of mathematical analysis, which will be a real find for students, graduate students and everyone who is interested in the theory and practice of partial derivatives equations. This work is not just a textbook, but a whole encyclopedia of knowledge that reveals complex topics in an accessible and understandable language. In his book, Yegorov offers readers a unique approach to the study of partial-derivative equations, combining theoretical foundations with practical examples. It covers a wide range of topics ranging from basic concepts to more complex concepts such as decision methods, the existence and uniqueness of solutions, and the application of equations in various fields of science and technology. Each chapter is filled not only with mathematical calculations, but also with living examples from real life, which allows the reader to see how theoretical knowledge is applied in practice. The book will be especially interesting for students of mathematical, physical and engineering faculties, as well as graduate students and teachers who are looking for high-quality and modern materials for learning. If you are passionate about mathematics, physics or engineering, then this publication will become your reliable companion in the study of complex topics. Egorov masterfully explains how partial-derivative equations can model real-world processes, such as heat propagation, fluid motion, or population dynamics. The topics raised in the book cover not only theoretical aspects, but also practical applications of partial-derivative equations in various fields of science. Readers will be able to learn about numerical decision methods, how to use computer technology for analysis and modeling, as well as the latest advances in this field. This makes the book relevant and useful for those seeking to be at the forefront of scientific research and technology. The style of the author is distinguished by clarity and logical presentation, which allows even the most complex concepts to be perceived easily and at ease. Egorov is not only an author, but also an experienced teacher who knows how to convey material to students. His lectures are always filled with lively examples and interesting tasks, which makes the learning process fascinating. In addition to this book, readers can read his other works, which are also devoted to mathematical analysis and the theory of differential equations. "Lectures on partial-derivative equations. Additional Chapters" is not just a textbook, but a real find for those who want to deepen their knowledge in the field of mathematics. The book will be an excellent addition to the library of any student or specialist who seeks to improve himself and broaden his horizons. If you are looking for high-quality and informative material on partial derivatives equations, then this edition is definitely worth your attention. Do not miss the opportunity to discover the world of mathematical analysis together with Yuri Vasilievich Egorov and his fascinating lectures!