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Chapter 5 The Real Numbers

All truths are easy to understand once they are discovered; the point is to discover them.
―Galileo Galilei, astronomer & physicist
In this chapter we will take a deep dive into the structure of the real numbers by building up the multitude of properties you are familiar with by starting with a collection of fundamental axioms. Recall that an axiom is a statement that is assumed to be true without proof. These are the basic building blocks from which all theorems are proved. It is worth pointing out that one can carefully construct the real numbers from the natural numbers. However, that will not be the approach we take. Instead, we will simply list the axioms that the real numbers satisfy.