公式与文本之间的距离

Question

在下面的代码中，您可以看到公式和文本之间的距离异常大。 是否可以减小该距离？

\documentclass[12pt]{article}
\usepackage[a4paper,text={16.5cm,25.2cm},centering]{geometry}
%\usepackage[utf8]{inputenc} % no longer needed
%\usepackage[english]{babel} % not actually needed

%\usepackage{amsmath}
\usepackage{mathtools}% also loads amsmath
\usepackage{amssymb}
\usepackage{amsthm}
\usepackage{dsfont}
\usepackage{nccmath}
\usepackage{cancel}
\usepackage{enumerate}  


\usepackage{mdframed}
\usepackage{graphicx}

\usepackage{setspace}

% for mock text, not needed in a real document
\usepackage{lipsum}

% must be last almost all the times
\usepackage{hyperref}

\onehalfspacing
%\doublespacing

\newcommand{\isEquivTo}[1]{\underset{#1}{\sim}}

\newcommand{\RN}[1]{%
  \textup{\uppercase\expandafter{\romannumeral#1}}%
}

\newtheorem{theorem}{Theorem}
\newmdtheoremenv{theo}[theorem]{Theorem}
%\newmdtheoremenv{lem}[lemma]{Lemma}
%\newtheorem{lemma}[theorem]{Lemma}
\newtheorem{lemma}{Lemma}
\newtheorem{exercise}{Exercise}
\newtheorem{claim}{Claim}
\newtheorem{corollary}{Corollary}
\newtheorem{definition}{Definition}
\newtheorem{example}{Example}

\newtheorem{remark}{Remark}

%\newcommand\smallO{%
 % \mathchoice
  %  {{\scriptstyle\mathcal{O}}}% \displaystyle
   % {{\scriptstyle\mathcal{O}}}% \textstyle
    %{{\scriptscriptstyle\mathcal{O}}}% \scriptstyle
    %{\scalebox{.7}%{$\scriptscriptstyle\mathcal{O}$}}%\scriptscriptstyle
  %}

\title{}
\author{}
\date{}

\begin{document}

\maketitle

 This follows form the triangle inequality, since
\begin{equation*}
|\chi(x_1+x_2)-1|=|\chi(x_1)\chi(x_2)-\chi(x_1)\overline{\chi(x_1)}|=|\chi(x_2)-\overline{\chi(x_1)}|,
\end{equation*}
where.

\end{document}