QuickMathNote.tex

\documentclass[22pt,a4paper,notitlepage]{article}

%% Use your favourite packages here
\usepackage[margin=0.8in]{geometry}
\usepackage[T1]{fontenc}
\usepackage{times} 
\usepackage{amsmath, amssymb, amsfonts} 
\usepackage{braket}
\usepackage{cancel}
\usepackage{hyperref}

\begin{document}
\title{Title of your quick note}
\author{Your Name}
\date{\today} % Can also use a custom date
\maketitle

%%=================Start====================%%

\noindent % Start line without indentation
Write sentences using words and equations such as $x^3 - y = 0$. We can also write standalone equations like below

$$ H \ket{\Psi} 
= E \ket{\Psi}.
$$
\\ % Line break without indentation
More words.

%% Use sections to organize
\section{Section with numbers}

   \subsection{Subsection with numbers}

\section*{Section without numbers}

   \subsection*{Subsection without numbers}

   Use \textit{align} to write multiple lines of equations as below

   \begin{align*}
   \ket{\Psi} 
   &:= \sum_{\mu} \: c_{\mu} \ket{\mu},
   \\
   E 
   &= \frac{\braket{\Psi | H | \Psi}}{\braket{\Psi|\Psi}},
   \end{align*}
   more words just below equations.
   \\ \\ % Line break without indentation
   We can also include equation numbers.
   
   \begin{align}
   \ket{\Psi} 
   &:= \sum_{\mu} \: c_{\mu} \ket{\mu},
   \\
   E 
   &= \frac{\braket{\Psi | H | \Psi}}{\braket{\Psi|\Psi}}.
   \end{align}
   
   \noindent
   We can create hyperlinks using \href{https://www.overleaf.com/learn/latex/Hyperlinks}{hyperref} and also \cancel{strikethrough} using the \textit{cancel} package.
   

\end{document}