We are all familiar with numbers and are these the most basic, most foundational concept in mathematics? Mathematicians use set theory as the basic building blocks of so much of math. In this video we are going to see how we can think of numbers and functions in terms of sets. 0:00 The Definition Problem 1:44 Set Theory 3:50 Numbers in Set Theory 6:48 Functions in Set Theory COURSE PLAYLISTS: ►CALCULUS I: ► CALCULUS II: ►MULTIVARIABLE CALCULUS (Calc III): ►DIFFERENTIAL EQUATIONS (Calc IV): ►DISCRETE MATH: ►LINEAR ALGEBRA: OTHER PLAYLISTS: ► Learning Math Series ►Cool Math Series: BECOME A MEMBER: ►Join: MATH BOOKS & MERCH I LOVE: ► My Amazon Affiliate Shop: SOCIALS: ►Twitter (math based): ►Instagram (photography based):