Generate equations with label in sharelatex - syntax

Question

I have made the following equation in sharelatex:
\[ \frac{\delta u}{\delta x} + \frac{\delta v}{\delta y} = 0 \]
How can I automatically label this equation with a number?
I have the following before the beginning of my document. My code is a bit messy, but I hope it can show what the problem is that prevents equation from working.
How can I automatically label this equation with a number?
I have the following before the beginning of my document. My code is a bit messy, but I hope it can show what the problem is that prevents equation from working.
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage{nomencl}
\makenomenclature
\usepackage[english]{babel}
\usepackage[round]{natbib}
\usepackage{natbib}
\setcitestyle{square}
\usepackage[utf8]
\usepackage[table, svgnames, dvipsnames]{xcolor} %color row
\usepackage{makecell}
\renewcommand\theadfont{\normalsize}
\usepackage{caption}
\usepackage{siunitx}
\usepackage[justification=centering,font=small,labelfont=bf,tableposition=top]{caption}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[bottom]{footmisc}
\usepackage[margin=1.1in]{geometry}
\geometry{a4paper,total={170mm,257mm},left=22mm,right=22mm,top=30mm,bottom=20mm}
\usepackage{booktabs}
\usepackage[numbers]{natbib}
\usepackage{float}
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{array}
\usepackage{blindtext}
\usepackage{color}
\usepackage{comment}
\usepackage{fancyhdr}
\usepackage{float}
\usepackage{footnote}
\usepackage{gensymb}
\usepackage{graphicx}
\usepackage{graphics}
\usepackage{hyperref}
\usepackage{lastpage}
\usepackage{listings}
\usepackage{longtable}
\usepackage{nomencl}
\usepackage{pifont}
\usepackage{subcaption}
\usepackage{subfiles}
\usepackage{tablefootnote}
\usepackage{times}
\usepackage{tikz}
\usepackage{watermark}
\usepackage{pdfpages}
\usepackage[pdftex]{graphicx}
\usepackage{graphicx,subcaption}
%for the tables
\usepackage[margin=1in,letterpaper]{geometry} % text block parameters
\usepackage{tabularx,siunitx,booktabs}
\usepackage[skip=0.5\baselineskip]{caption}
\usepackage{newtxtext,newtxmath}
\newcommand\mX[1]{\multicolumn{1}{X}{#1}} % handy shortcut macros
\newcommand\mcc[1]{\multicolumn{2}{c}{#1}}
\newcommand\mcl[1]{\multicolumn{2}{l}{#1}}\usepackage[margin=1in,letterpaper]{geometry} % text
\usepackage{multirow}
\graphicspath{{./Figures/}}
\setlength\parindent{0pt}
\usetikzlibrary{arrows,calc,positioning,shadows,shapes}
\newcommand{\cmark}{\textcolor{green!80!black}{\ding{51}}}
\newcommand{\xmark}{\textcolor{red}{\ding{55}}}
\usepackage{enumitem}%make indented dots
\usepackage{textcomp}
\usepackage{amsmath}
% Array commands, depends on \usepackage{array}
\newcolumntype{L}[1]{>{\raggedright\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}
\newcolumntype{C}[1]{>{\centering\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}
\newcolumntype{R}[1]{>{\raggedleft\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}
% Something with captions, depends on \usepackage{caption}
\DeclareCaptionLabelFormat{andtable}{#1~#2 \& \tablename~\thetable}
% Front page settings depends on \usepackage{fancyhdr}
\pagestyle{fancy}
\lhead{Name}
\newcommand{\specialcell}[2][c]{%
\begin{tabular}[#1]{#{}c#{}}#2\end{tabular}}
\rhead{Project}
\renewcommand{\baselinestretch}{1.3} % Line spacing
% Color settings depends on \usepackage{color}
\definecolor{mygreen}{RGB}{28,172,0} % color values Red, Green, Blue
\definecolor{mylilas}{RGB}{170,55,241}
\begin{document}
I have tried several codes but nothing is working. Not even the equation option.
Thanks for help in advance!

Answer 1

There are several serve errors in your preamble. You must fix them, if you ignore them tex only syntax checks the rest of the document and you end up with something that might or might not be a valid pdf
you must not load the same package multiple times with different options. The log file will clearly tell you about the error because of an option clash. In your example this concerns geometry, graphicx and natbib
the line \usepackage[utf8] is an syntax error. You must give a package name, not just an option
many other packages are loaded multiple times and some of the options are outdated, you should take a bit of time and clean up this preamble
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage{nomencl}
\makenomenclature
\usepackage[english]{babel}
\usepackage[round]{natbib}
%\usepackage{natbib}
\setcitestyle{square}
%\usepackage[utf8]
\usepackage[table, svgnames, dvipsnames]{xcolor} %color row
\usepackage{makecell}
\renewcommand\theadfont{\normalsize}
\usepackage{caption}
\usepackage{siunitx}
\usepackage[justification=centering,font=small,labelfont=bf,tableposition=top]{caption}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[bottom]{footmisc}
\usepackage[margin=1.1in]{geometry}
\geometry{a4paper,total={170mm,257mm},left=22mm,right=22mm,top=30mm,bottom=20mm}
\usepackage{booktabs}
%\usepackage[numbers]{natbib}
\usepackage{float}
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{array}
\usepackage{blindtext}
\usepackage{color}
\usepackage{comment}
\usepackage{fancyhdr}
\usepackage{float}
\usepackage{footnote}
\usepackage{gensymb}
\usepackage{graphicx}
\usepackage{graphics}
\usepackage{hyperref}
\usepackage{lastpage}
\usepackage{listings}
\usepackage{longtable}
\usepackage{nomencl}
\usepackage{pifont}
\usepackage{subcaption}
\usepackage{subfiles}
\usepackage{tablefootnote}
\usepackage{times}
\usepackage{tikz}
\usepackage{watermark}
\usepackage{pdfpages}
%\usepackage[pdftex]{graphicx}
%\usepackage{graphicx,subcaption}
%for the tables
%\usepackage[margin=1in,letterpaper]{geometry} % text block parameters
\usepackage{tabularx,siunitx,booktabs}
\usepackage[skip=0.5\baselineskip]{caption}
\usepackage{newtxtext,newtxmath}
\newcommand\mX[1]{\multicolumn{1}{X}{#1}} % handy shortcut macros
\newcommand\mcc[1]{\multicolumn{2}{c}{#1}}
\newcommand\mcl[1]{\multicolumn{2}{l}{#1}}
%\usepackage[margin=1in,letterpaper]{geometry} % text
\usepackage{multirow}
\graphicspath{{./Figures/}}
\setlength\parindent{0pt}
\usetikzlibrary{arrows,calc,positioning,shadows,shapes}
\newcommand{\cmark}{\textcolor{green!80!black}{\ding{51}}}
\newcommand{\xmark}{\textcolor{red}{\ding{55}}}
\usepackage{enumitem}%make indented dots
\usepackage{textcomp}
\usepackage{amsmath}
% Array commands, depends on \usepackage{array}
\newcolumntype{L}[1]{>{\raggedright\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}
\newcolumntype{C}[1]{>{\centering\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}
\newcolumntype{R}[1]{>{\raggedleft\let\newline\\\arraybackslash\hspace{0pt}}m{#1}}
% Something with captions, depends on \usepackage{caption}
\DeclareCaptionLabelFormat{andtable}{#1~#2 \& \tablename~\thetable}
% Front page settings depends on \usepackage{fancyhdr}
\pagestyle{fancy}
\lhead{Name}
\newcommand{\specialcell}[2][c]{%
\begin{tabular}[#1]{#{}c#{}}#2\end{tabular}}
\rhead{Project}
\renewcommand{\baselinestretch}{1.3} % Line spacing
% Color settings depends on \usepackage{color}
\definecolor{mygreen}{RGB}{28,172,0} % color values Red, Green, Blue
\definecolor{mylilas}{RGB}{170,55,241}
\begin{document}
\begin{equation}
\frac{\delta u}{\delta x} + \frac{\delta v}{\delta y} = 0
\end{equation}
\end{document}