\begin
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\documentclass[12pt,fleqn]{book}
\usepackage{amsmath} %utk masuk begin{align}
\usepackage{amsxtra}%supaya \eqref
\usepackage{amsopn}%supaya dapat declare benda baru \citep
\usepackage{amsbsy}
\usepackage{amstext}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsthm}
\usepackage{shadow}% kotak shadow
\usepackage{chaptengah}
\usepackage{curves}
\usepackage{graphicx}
\usepackage{color}%masukan color
\usepackage{maple2e}
%\usepackage{flafter}
\usepackage{afterpage}
%\usepackage{tocloft}
\usepackage{XTocinc}% utk center contents, masuk chapter, topic dan page number
% bila masuk ini jadi bold tex
%\usepackage[bottom=0.5in]{geometry}
\usepackage{lipsum}
\usepackage{imakeidx}
\makeindex
%-----------------------
\usepackage{titletoc}
\makeatletter
\renewcommand*{\@dotsep}{999}% untuk buang dotted line besar nombor spt spt 999
\makeatother
\newtheorem{ts}{Task}
%------------------------
%--------%---
%
%\titlecontents{section}[1.5em]
% {\bfseries}
%{\contentslabel{2em}}
%{\hspace*{-2.3em}}
%{\titlerule*[1pc]{.}\contentspage}
\usepackage{natbib}
%\makeindex
\citestyle{mn}%\documentclass[11pt,fleqn]{report}
%\usepackage{mn}
\theoremstyle{plain}
\newtheorem{thm}{Theorem}[section]
\newtheorem{cor}[thm]{Corollary}
%\newtheorem{lem}[thm]{Lemma}
\newtheorem{prop}[thm]{Proposition}
%
%\theoremstyle{Example}
\newtheorem{exl}{Example}[section]
%
\newcommand{\sn}{\textbf{Solution}}
\theoremstyle{plain}
%\newtheorem{thm}{Theorem}[section]
%\newtheorem{cor}[thm]{Corollary}
%\newtheorem{lem}[thm]{Lemma}
%\newtheorem{prop}[thm]{Proposition}
%
\theoremstyle{Example}
%\newtheorem{exl}{Example}%section]
\theoremstyle{Question}
\newtheorem{qs}{Question}
\theoremstyle{Task}
%\newtheorem{ts}{Task}
\theoremstyle{Solution Task}
\newtheorem{sots}{Answer}
\theoremstyle{Exercise}
\newtheorem{ex}{Exercise}%section]
%
\theoremstyle{definition}
\newtheorem{defn}{Definition}[section]
%
\theoremstyle{solution}
\newtheorem{so}{Solution}
%\theoremstyle{}
%\newtheorem{qs}{}[]
\theoremstyle{remark}
\newtheorem{rem}{Remark}[section]
\newcommand{\Lim}{\mathop{\mathrm{\lim}}\limits}
%
%\theoremstyle{Problem Solving}
\newtheorem{prob}{Problem Solving}[chapter]
%
%\theoremstyle{Solution to Problem}
\newtheorem{sop}{Solution to Problem Solving}[chapter]
%
%\theoremstyle{Solution}
%\newtheorem{so}{Solution}[section]
%---------
%
%\newcommand{\Lim}{\mathop{\mathrm{\lim}}\limits}
\newcommand{\A}{\mathop{\mathrm{A}}\limits}
\newcommand{\B}{\mathop{\mathrm{B}}\limits}
\newcommand{\C}{\mathop{\mathrm{C}}\limits}
\newcommand{\D}{\mathop{\mathrm{D}}\limits}
\newcommand{\E}{\mathop{\mathrm{E}}\limits}
\newcommand{\ra}{\mathop{\longrightarrow\longrightarrow}\limits}
%\theoremstyle{Question}
%\newtheorem{qs}{Question}
%------------------
%\theoremstyle{definition}
%\newtheorem{defn}{Definition}[section]
%
%\theoremstyle{Key Term}
\newtheorem{term}{Key Term}[section]
%\theoremstyle{remark}
%\newtheorem{rem}{Remark}[section]
%
%\newtheorem{exl}{Example}[section]
%\newtheorem{so}{Solution}[section]
%\newtheorem{la}{\mathfrak{L}\{\}}[section]
\newcommand{\lap}{\mathop{\mathfrak{L}}\limits}
%--------------------
\newcommand{\mut}{\mathop{\mathfrak{U}}\limits}
\newcommand{\lapi}{\mathop{\mathfrak{L}^{-1}}\limits}
%---------
\oddsidemargin 0.6cm \evensidemargin 0in
%\addtolength{\hoffset}{3.0cm}
\marginparwidth 15pt \marginparsep 7pt
\topmargin 1.5cm %asal1.5
\headsep 1.0cm %asal 1.1
\addtolength{\voffset}{-2.6cm}%adjust 1.25m page no. dari tepi atas
\textheight 22.0cm \textwidth 16.0cm %asal 25.2
%\voffset=0.25cm
\headheight=13pt
\setcounter{chapter}{0}
\pagestyle{headings}
%\pagestyle{plain}
%\setcounter{page}{8}
\begin{document}
\setcounter{tocdepth}{4} %How many levels to include in TOC
\addtocontents{toc}{\protect\sloppy} %Keeps long chapters within page # margins
\pagenumbering{roman}
\tableofcontents
\include{chap1}
\include{chap2}
\include{chap3}
\include{chap5}
\include{chap4}
\include{chap6}
\include{chap7}
\bibliographystyle{mn}
\bibliography{cuba}
\printindex
\end{document}