# can't renew math command '\exp', why? [duplicate]

In the preamble of the main.tex file I've written \renewcommand{\exp}[1]{ \exp \left( {#1} \right) } so that the math function \exp automatically includes the round brackets. In the file I wrote simply $\exp{qV/kT}$. When I compile with pdflatex I get an error that says: TeX capacity exceeded, sorry [input stack size=5000] $\exp{}. What does that mean? I'm on Win7, TEXLive2013, TexStudio 2.6.6. From the log file:  (./cap7_formule.tex ! TeX capacity exceeded, sorry [input stack size=5000]. \exp #1-> \exp \left ( {#1} \right ) l.2$ \exp{}
\$
If you really absolutely need more capacity,
you can ask a wizard to enlarge me.

• In the words of the old joke: to understand recursion, you must first understand recursion. In simple-structured cases like this, you can't usefully have the command you're trying to (re)define in the definition itself. – Ulrich Schwarz Jan 12 '14 at 12:41
• Try to use a different name like \myexp. – user11232 Jan 12 '14 at 12:48