Add last lecture notes (Yes there's some missing)

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% File: 27-01-2022.tex
% Created: 12:36:49 Thu, 27 Jan 2022 EST
% Last Change: 12:36:49 Thu, 27 Jan 2022 EST
%
\documentclass[letterpaper]{article}
\usepackage{amsmath}
\usepackage{graphicx}
\usepackage{cancel}
\usepackage{amssymb}
\usepackage{listings}
\usepackage[shortlabels]{enumitem}
\usepackage{soul}
%\usepackage[smartEllipses,hashEnumerators,hybrid]{markdown}
%\usepackage{minted}
\usepackage{geometry}
\usepackage{dirtytalk}
\usepackage{lplfitch}
\geometry{portrait, margin=1in}
%\begin{minted}[linenos,bgcolor=LightGray]{[language]}
\date{01/27/2022}
\title{%
Starting Proofs\\
\large MATH--190--01: Discrete Mathematics for Computing}
\author{Blizzard MacDougall}
\begin{document}
\maketitle
\pagenumbering{arabic}
We have the following rules so far:
\begin{itemize}
\item $A=A$
\item $A=B\to B=A$
\item $[(A=B)\land (B=C)] \to (A=C)$
\item $\mathbb{Z}$ is all whole integers.
\item Integers are closed under $+,\ -,\ \times$ but not $\div$
\end{itemize}
There are two ways to prove statements.
\begin{itemize}
\item \textit{Constructive proofs} - Find the thing, or show how to.
\begin{itemize}
\item Perfect numbers exist (There are numbers which is the sum of its proper divisors.) 6
\item Suppose $r,s\in \mathbb{Z}$. Prove that there exists an integer $k$ such that $24r+4s=2k$
\end{itemize}
\item \textit{Nonconstructive proofs} - Show that it has to exist, but don't say how or what it is.
\begin{itemize}
\item Given any set of 2 consecutive integers, one of them is even.
\item Roth's theorem. If $\alpha$ is any algebraic irrational number, then there are
only finitely many rational numbers such that
$\left|\alpha - \frac{p}{q}\right| <\frac{1}{q^{2+\epsilon}}$
\end{itemize}
\end{itemize}
The easiest way to disprove a universal statement is that you have to show the inverse.
That is, you have to find one instance where it isn't true.
\emph{Proving} a universal statement is significantly harder. If $\mathbb{D}$ is finite,
the method of exhaustion is easiest. However, the best technique is to generalize from a generic
parameter. That is, pick a general element, then show that it satisfies the statement.
Generally $x$ is reserved for a real number, and $n$ is reserved for integer use.
To prove a $\forall x\in \mathbb{D}$:
\begin{enumerate}
\item Express the statement to be proved in the form:
\begin{equation}
\forall x\in \mathbb{D} P(x)\to Q(x)
\end{equation}
\item "Suppose $x\in \mathbb{D} \land P(x)$"
\item Prove $Q(x)=\top$
\end{enumerate}
Example proof:\\
For all integers $m$ and $n$, if $m$ and $n$ are odd, then $m\times n$ is odd.\\
Proof: Let $m$ and $n$ be odd integers.\\
Since $m$ is odd, there is an integer $r$ such that $m=2r+1$.\\
Similarly, there is an integer $s$ such that $n=2s+1$.\\
Since $m\times n = (2r+1)(2s+1) = 4rs+2r+2s+1 = 2(2rs+r+s) + 1$\\
Let $k=2rs+r+s$. Note that $k$ is an integer.\\
$\therefore m\times n=2k+1$, so $m\times n$ is odd. QED
\end{document}

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% File: 20-01-2022.tex
% Created: 12:28:35 Thu, 20 Jan 2022 EST
% Last Change: 12:28:35 Thu, 20 Jan 2022 EST
%
\documentclass[letterpaper]{article}
\usepackage{amsmath}
\usepackage{graphicx}
\usepackage{cancel}
\usepackage{amssymb}
\usepackage{listings}
\usepackage[shortlabels]{enumitem}
\usepackage{soul}
%\usepackage[smartEllipses,hashEnumerators,hybrid]{markdown}
\usepackage{geometry}
\usepackage{dirtytalk}
\usepackage{lplfitch}
\geometry{portrait, margin=1in}
%\begin{minted}[linenos,bgcolor=LightGray]{[language]}
\date{01/20/2022}
\title{%
LectureName\\
\large MATH--190--01 : Discrete Mathematics for Computing}
\author{Blizzard MacDougall}
\begin{document}
\maketitle
\pagenumbering{arabic}
\end{document}