# Theorem Class Environments

In this template, we defined four categories of theorem class environments

• Theorem Environment: including title and contents, numbering within chapter. There are three types depending on the format
• definition environment, the color is main;
• theorem, lemma, corollary environment, the color is second;
• proposition environment, the color is third.
• Example Environments: including example, exercise, problem environment, auto numering within chapter.
• Proof Environment: including proof, note environment, they contain introductory symbol (note environment) or ending symbol (proof environment).
• Conclusion Environments: including conclusion, assumption, property, remark, solution environment, all of these begin with boldfaced words, and the contents are the same as a normal paragraph.

## Theorem Class Environments

The template uses the tcolorbox package to customize the theorem class environments, it is slightly different from the normal theorem environments. The usage is as follows:

\begin{theorem}{<theorem name>}{<label>}
The content of theorem.
\end{theorem}


The ﬁrst parameter <theorem name> is the name of the theorem, and the second parameter label is the label used in cross-reference with ref{thm:label}. Note that cross-references must be prefixed with thm:.

Other theorem class environments with the same usage are:

Environment Label text Prefix Cross-reference
definition label def \ref{def:label}
theorem label thm \ref{thm:label}
lemma label lem \ref{lem:label}
corrlary label cor \ref{cor:label}
proposition label pro \ref{pro:label}

## Cross-reference

The other three math environments can be used directly since there are no options for them, the example environment usage:

\begin{example}
This is the content of example environment.
\end{example}


These are all the same environments, except that

• example, exercise, problem environments numbering within chapter;
• note with introductory symbol, proof with ending symbol;
• conclusion environment with boldfaced keywords and normal paragraph content.