[Tex/LaTex] Math book: Exercise – Solution environment

environmentsexercises

If I use this code provided by a question formulate of Sebastian for exercise environment.

\documentclass{article}
\usepackage[most]{tcolorbox}
\usepackage{lipsum}

\newtcolorbox[auto counter]{problem}[2][]{%
breakable,
blankest,
enhanced,
attach boxed title to top left={yshift=-\tcboxedtitleheight},
left=\tcboxedtitlewidth+1mm,
top=0pt,
colback=white,
fonttitle=\bfseries\sffamily,
coltitle={cyan!60!black},
colbacktitle=white,
colframe=white,
title=\thetcbcounter, 
overlay unbroken and first={%
\node[fill=gray!30, inner sep=1pt, minimum width=\tcboxedtitlewidth, 
outer sep=0pt, text=cyan!60!black, anchor=north] at(title.south) 
{\foreach \i in {1,...,#2}{\if#2gt1{\,}\fi$\bullet$}};},#1}

\begin{document}

\lipsum[1]

\begin{problem}{1}
\lipsum[2]
\end{problem}

\begin{problem}{4}
\lipsum[3]
\end{problem}

\begin{problem}{2}
\lipsum[4]
\end{problem}

\end{document}

How could we create solutions environment, so we have at the end of the book solution of the exercises where each one have reference to chapter, page, number of exercise with the corresponding level of difficulty?

Best Answer

I suggest to you to read exercise package documentation.

There are the package options:

lastexercise if no references is given for an answer, then the answer is supposed to refer to the last exercise (see section 2.1).

and

answerdelayed save the answers instead of typeset them. The answers can be included later in the document with the command \shipoutAnswer.

and the Exercise environment option:

difficulty The difficulty of the exercise (a number). It will be available later with the counter \ExerciseDifficulty.

You can start with this simple example and then make your customization. As you can see, if you write your Answer environment immediately after the corresponding Exercise, the answer is automatically joined to the previous exercise.

\documentclass[11pt]{book}
\usepackage[lastexercise,answerdelayed]{exercise}

\usepackage{lipsum}

\begin{document}

    \chapter{Test 1}

    \lipsum[1]

    \section{Problems}

    \begin{Exercise}[difficulty={1}]
        My easy exercise.
    \end{Exercise}
    \begin{Answer}
        My answer to my easy exercise.
    \end{Answer}

    \chapter{Test 2}

    \lipsum[1]

    \section{Problems}
    \begin{Exercise}[difficulty={2}]
        My difficult exercise.
    \end{Exercise}
    \begin{Answer}
        My answer to my difficult exercise.
    \end{Answer}

    \chapter{Solutions}

    \shipoutAnswer

\end{document}

Related Solutions

[Tex/LaTex] How to use figure inside a exercise environment

There is no requirement to place an image (using \includegraphics, say) inside a figure environment. The figure environment is merely a floating placeholder. So, you can just put your image inside a center environment to centre it on the page, and even add a caption using \captionof from the caption package.

enter image description here

\documentclass{article}
\usepackage{caption}% http://ctan.org/pkg/caption
\usepackage{exercise}% http://ctan.org/pkg/exercise
\begin{document}

\begin{Exercise}[title={foo}, label=ex1]
A tough question.
\end{Exercise}

\begin{Answer}[ref={ex1}]
A smart answer.

\begin{center}
  %\includegraphics[totalheight=0.2\textheight]{couetteFlowFig1.png}
  \rule{150pt}{100pt} \par
  \captionof{figure}{This is a figure caption.}
  \label{fig:ex1}
\end{center}
\end{Answer}

\end{document}

In the above example, I've replaced the image with a rectangular block to simulate the image, but it will work with \includegraphics as well (for which you will require \usepackage{graphicx} - the graphicx package).

The problem originates from inserting figure inside Exercise. Or, more generally, a float inside a non-floating (or restrictive) environment. Therefore, removing the floating environment enables the compilation to succeed.

[Tex/LaTex] An inline exercise environment

Here is an implementation that provides a \exinline command, taking a label argument to produce the relevant text.

Sample output

\documentclass{article}

\usepackage{amsthm}

\newtheorem{theorem}{Theorem}[section]
\newtheorem{exercise}[theorem]{Exercise}

\newcommand{\exinline}[1]{(\refstepcounter{theorem}Exercise~\thetheorem\label{#1})}

\begin{document}

\section{Euler's Theorem}

Some text.

\begin{theorem}[Euler]
  \label{thm:Euler}
  This is Euler's theorem.
\end{theorem}

\begin{proof}
  The proof of this theorem is left as an exercise \exinline{ex:Euler}.
\end{proof}

\begin{exercise}
  \label{ex:extra}
  Reformulate the theorem.
\end{exercise}

Here is the solution to Exercise~\ref{ex:Euler}.  By\dots

Note that Exercise~\ref{ex:extra} requires you to provide another formulation
of Theorem~\ref{thm:Euler}.

\end{document}

Note in this example Exercises and Theorems share the same counter. If that is not the case, you need to replace the theorem counter in definition with the appropriate counter, and change \thetheorem correspondingly. E.g. if exercises have their own number, declared via \newtheorem{exercise}{Exercise}[section], the command definition should read

\newcommand{\exinline}[1]{(\refstepcounter{exercise}Exercise~\theexercise\label{#1})}

If you are using cleveref for references then a small modification is needed to the refstepcounter command so \cref picks up the correct name.

\documentclass{article}

\usepackage{amsthm}
\usepackage[capitalize]{cleveref}

\newtheorem{theorem}{Theorem}[section]
\newtheorem{exercise}[theorem]{Exercise}

\newcommand{\exinline}[1]{(\refstepcounter[exercise]{theorem}Exercise~\thetheorem\label{#1})}

\begin{document}

\section{Euler's Theorem}

Some text.

\begin{theorem}[Euler]
  \label{thm:Euler}
  This is Euler's theorem.
\end{theorem}

\begin{proof}
  The proof of this theorem is left as an exercise \exinline{ex:Euler}.
\end{proof}

\begin{exercise}
  \label{ex:extra}
  Reformulate the theorem.
\end{exercise}

Here is the solution to \cref{ex:Euler}.  By\dots

Note that \cref{ex:extra} requires you to provide another formulation
of \cref{thm:Euler}.

\end{document}

This produces the same output as the first example, with cleveref correctly providing the names.

Best Answer

Related Solutions

[Tex/LaTex] How to use figure inside a exercise environment

[Tex/LaTex] An inline exercise environment

Related Question