real functionRealFunction2004-09-24 03:10:482007-07-22 03:15:27Topicfunction% this is the default PlanetMath preamble. as your knowledge
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% define commands hereA {\em real function} is a function from a subset of $\mathbb{R}$ to $\mathbb{R}$.
Without imposing extra conditions, there is really not much one can say about real
functions. Therefore, the usual procedure is to select some subclass of real
functions according to some criterion such as differentiability or integrability
and focus attention on this subclass. There follows a list of such criteria:
\begin{itemize}
\item elementary function
\item
\end{itemize}