Kdtyjb

I'm editing a document whose preamble starts with

documentclass [12pt, a4paper]{extbook}

I wish the chapter 'Introduction and its sections' appear in table
contents at the beginning of the text before the unnumbered chapter 1.

I also would like a chapter that I call 'Prelude' and its sections' appear in table
contents at the beginning of the text before the unnumbered chapter 1.

How can I do this?

Introduction .................................................
.................

             nontechnical introduction .........................



             intrudução technique .................................



             structure of the thesis ....................................

Chapter 1 ................................................
..................

             Section 1 ..................................



             Section 2 ..................................



             Section 3 ..................................

Chapter 9 ................................................
................

             Section 1 ..................................



             Section 2 ..................................



             Section 3 ..................................

Prelude
..................................................................

             Other open issues .........................



             New techniques ............................

I think you are looking for the starred versions of the section, part etc and a addcontentsline{toc}{}{}.

For example:

documentclass[12pt,a4paper]{extbook}



begin{document}

    tableofcontents

    chapter*{Introduction}addcontentsline{toc}{chapter}{Introduction}

        section*{nontechnical introduction}addcontentsline{toc}{section}{nontechnical introduction}

        section*{intrudução technique}addcontentsline{toc}{section}{intrudução technique}

        section*{structure of the thesis}addcontentsline{toc}{section}{structure of the thesis}



    chapter{Chapter 1}

        section{Section 1}

        section{Section 2}



    chapter{Chapter 9}

        section{Section 1}

        section{Section 2}



    chapter*{Prelude}addcontentsline{toc}{chapter}{Prelude}

        section*{Other open issues}addcontentsline{toc}{section}{Other open issues}

        section*{New techniques}addcontentsline{toc}{section}{New techniques}

end{document}

An easier solution is to use KOMA-script and the scrbook-class and utilise the addchapand addsec commands. They are similar to the standard commands chapter and section except that they are unnumbered. They produce both a running
head and an entry in the table of contents.

documentclass{scrbook}



begin{document}

    tableofcontents

    addchap{Introduction}

        addsec{nontechnical introduction}

        addsec{intrudução technique}

        addsec{structure of the thesis}



    chapter{Chapter 1}

        section{Section 1}

        section{Section 2}



    chapter{Chapter 9}

        section{Section 1}

        section{Section 2}



    addchap{Prelude}

        addsec{Other open issues}

        addsec{New techniques}

end{document}