t is a moment of great pleasure and immense satisfaction for me to express deep

 gratitude and gratefulness to my father Er VK Agarwal and my mother Smt Asha

Agarwal for inspiring me to bring out this book.

I am especially thankful to Shri RP Singal Ji, Chairman, RP Educational Trust, for

his all time support and encouragement. My special thanks to Er Bharat Singal, and

Anuj Singal, Secretary, RP Educational Trust, for inspiring me to bring out this book.

I am indebted to Shri DL Mittal, Director, RPIIT Technical and Medical Campus, for

his motivation.

I am also thankful to CBS Publishers and Distributors. I would like to put on record

the sincere efforts of Mr YN Arjuna (Senior Vice President Publishing, Editorial and Publicity)

and his team comprising of Ms Ritu Chawla (GM Production), Mr Parmod Kumar

(DTP Operator) and Mr Rohan Prasad (Graphic Designer), for bringing out the book

in the present form.

My completion of this project could not have been accomplished without the support

of my loving daughter Shreya and son Vaidish who have allowed me time away from

the writing and research work.

Last but not the least, I express my love to my wife Dr Shilpi for her caring, motivating

and supportive nature. Her encouragement was always there when the times got rough.

It was a great comfort and relief that she kept me away from our household activities

during the entire tenure of writing and research work.

To my numerous students, whom I cannot possibly name individually, I thanks for

their class interactions which have been the guiding spirit in selection of the subject

matter and its logical arrangement.

Gaurav Agarwal

Acknowledgements

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