[Tex/LaTex] Limits used as exponents — how to write under the limit symbol without using \displaymath

math-modemath-operators

If one needs to write a limit as an exponent, one might have this dilemma: if you use \displaymath, "x to infinity" will be nicely printed under the lim symbol, but your exponent will be using the normal font and will appear very big on the page. If you take out the \displaymath instruction, the exponent will use the small font, but now the part "x to infinity" is not a subscript to the "lim" symbol anymore, it just follows it. Trying to use any font size instructions with \displaystyle, or actually inside the math mode, does not seem to work for me! Does anybody know any trick to get around this?

This is the horrible expression I am fighting with (might be easier to make my point this way):

$e^{\left(\, \displaystyle \lim_{x \,\rightarrow\, \infty} 
\frac{\, 2x \sin{\frac{1}{x}} \,}{ 1 \,-\, \sin{\frac{1}{x}}} 
\,\right) } \,;$

I can't get the last exponent to behave, because it contains the limit (it's the last exponent, the one for the number e). If I take out the \displaystyle, the limit gets messed up, as explained above.

Best Answer

I would suggest you to use the exp(...) notation instead of e^{}; you can force the below position for the limit using \limits; since you are writing this expresion as in-line math I would also suggest using 1/x instead of \frac{1}{x}:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

$\exp\left(\lim\limits_{x\rightarrow\infty} \frac{\, 2x \sin(1/x) \,}{ 1 - \sin(1/x)}\right)$

\end{document}

enter image description here

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