Differential calculus is a branch of mathematics that deals with the study of rates of change, slopes, tangents, maxima and minima, and other related concepts. It is an essential tool for many fields of science and engineering, such as physics, chemistry, biology, economics, and computer science.

One of the most popular and widely used textbooks for differential calculus is Differential Calculus by B.C. Das and B.N. Mukherjee. This book was first published in 1938 and has been revised and updated several times since then. It covers all the topics of differential calculus in a rigorous and comprehensive manner, with numerous examples, exercises, and solved problems. The book also includes chapters on differential equations, infinite series, and applications of differential calculus.

The book is suitable for undergraduate and postgraduate students of mathematics, as well as for students preparing for competitive examinations such as JEE, GATE, NET, etc. The book is written in a clear and concise style, with a logical and coherent presentation of the concepts and methods. The book also provides historical notes and biographical sketches of some of the famous mathematicians who contributed to the development of differential calculus.

The book is available in both print and digital formats. However, many students prefer to download the PDF version of the book for free from various online sources. This allows them to access the book anytime and anywhere, without having to carry a heavy hard copy. Moreover, downloading the PDF version of the book also saves money and paper.

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