% use [nosolutions] flag to hide solutions.
% use [solutions] flag to show solutions.
\documentclass[
	solutions,
	singlenumbering
]{./ormc_handout}


\title{The Size of Sets}
\subtitle{Prepared by Mark on \today{}}

\begin{document}

	\maketitle

	\section{Set Basics}

	\definition{}
	A \textit{set} is a collection of objects. \par
	If $a$ is an element of set $S$, we write $a \in S$. This is pronounced \say{$a$ in $S$.} \par
	The position of each element in a set or the number of times it is repeated doesn't matter. \par
	All that matters is \textit{which} elements are in the set.

	\vspace{2mm}

	We say two sets $A$ and $B$ are equal if every element of $A$ is in $B$, and every element of $B$ is in $A$. This is known as the \textit{principle of extensionality.}

	\problem{}
	Convince yourself that $\{a, b\} = \{b, a\} = \{a, b, a, b, b\}$.

	\begin{solution}
		This is a solution.
	\end{solution}

\end{document}