Calculus Made Easy, Chapter 6. How do we differentiate polynomials? How do we deal with addition, subtraction, multiplication and division of entire functions? Each deriviative is approaced from first principles.
0:15 Addition
2:02 Subtraction
2:31 Multiplication (Product Rule)
6:09 Division (Quotient Rule)
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https://www.youtube.com/watch?v=vYz8A4Pc11Q