How can I have set double limits for a lime as shown here

At the moment I am using this syntax
\begin{equation}
\displaystyle{ \lim \limits_{a \to b}= smt}
\end{equation}
Regards,
Marin
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\substack
(centered) and/or {subarray}
(horizontal alignment can be specified) for that, e.g.,
Code: Select all
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{equation}
\lim \limits_{\substack{%
a \to -\infty\\
b \to \infty}} = \lim\limits_{\begin{subarray}{l}
a \to -\infty\\
b \to \infty
\end{subarray}} = smt
\end{equation}
\end{document}
NEW: TikZ book now 40% off at Amazon.com for a short time.
And: Currently, Packt sells ebooks for $4.99 each if you buy 5 of their over 1000 ebooks. If you choose only a single one, $9.99. How about combining 3 LaTeX books with Python, gnuplot, mathplotlib, Matlab, ChatGPT or other AI books? Epub and PDF. Bundle (3 books, add more for higher discount): https://packt.link/MDH5p