--- format: markdown toc: yes title: Mathematical Proof Study Notes ... # Texts - *Book of Proof*, Richard Hammack # Reading Notes ## *Hammack*, 25 Jan 2014 All of Mathematics can be described with sets. *set* : A collection of things. The things in the set are called *elements*. An example of a set: ${2,4,6,8}$ The set of all integers: $$ {\dots, -4, -3, -2, -1, 0, 1, 2, 3, 4, \dots} $$ The dots mean the expressed pattern continues. Sets of infinitely many members are *infinite*, otherwise they are *finite*. Sets are *equal* if they have exactly the same elements. E.g. ${2,4,5,8} = {4,2,8,6}$ but ${2,4,6,8} \neq {2,4,6,7}$. Uppercase letters often denote sets, e.g. $A = {1,2,3,4}$. To express membership, we use $\in$, as in $2 \in A$.