# How to have subscript below max in cases environment

Whit the following code the max subscript is displayed on the right of max, while I want it to be below. Removing the cases fixes the issue, but still I need it. How can I fix that ?

   $$f(i)=\begin{cases} 0, & \text{if S_{i} is empty}.\\ \max_{t_k \in S_{i}}\{f(k) + 42\}, & \text{otherwise}. \end{cases}$$

• You could use \max\limits_{...} or the dcases environment from mathtools. – campa Dec 3 '18 at 14:40
• \max\limits_{...} – David Carlisle Dec 3 '18 at 14:41

As mentioned in the comments, \max\limits_{} works well! However, if you want a general answer, read this answers (which is also mine):

\documentclass{article}
\usepackage{amsmath}
\begin{document}
$$f(i)=\begin{cases} 0, & \text{if S_{i} is empty}.\\ \underset{t_k \in S_{i}}{\max}\{f(k) + 42\}, & \text{otherwise}. \end{cases}$$
\end{document}


• No, \underset is the wrong tool for this. – egreg Dec 3 '18 at 15:04