What Is the Number e and How Do We Calculate It?

The Organic Chemistry Tutor

This educational video provides a comprehensive overview of the mathematical constant e, also known as Euler's number. It begins by defining e as an irrational number approximately equal to 2.718, commonly found in exponential functions and logarithms. The narrator then explores the origins of e through three distinct mathematical approaches: the formula for compound interest as the compounding frequency approaches infinity, the limit of (1 + n)^(1/n) as n approaches zero, and the infinite series of the reciprocals of factorials. Key themes include the relationship between discrete and continuous growth, the concept of limits and infinity in mathematics, and the unique properties of exponential functions in calculus. The video bridges the gap between algebraic financial formulas and advanced calculus concepts, demonstrating how a simple question about interest rates leads to the discovery of a fundamental constant of the universe. For educators, this video serves as an excellent bridge between Algebra II, Pre-Calculus, and Calculus. It visualizes abstract definitions, provides concrete numerical evidence for limits, and introduces the profound calculus properties of e^x—specifically that its slope and the area under its curve are equal to its value. This makes it a versatile tool for introducing the constant to beginners or deepening the understanding of advanced students studying derivatives and integrals.