Encyclopaedia of Differential Calculus has been written to meet the requirements of both Graduate and Post Graduate students of all Indian Universities. The Encyclopaedia is also useful for all Competitive Examinations. Attempt has been made to make the subject easy and understandable to the average students without sacrificing any rigor. Expansion of the Fundamental Principles is made clear and concise. The subject matter has been discussed in such a simple way that the student will find no difficulty to understand it. The proofs of various Theories and Examples have been given in minute details. Each chapter of this book contains complete theory and large number of solved examples sufficient problems have also been selected from various Indian Universities and competitive examination.