Table: Cases braces being overlapped by white when alternating colors used

Question

I would like to use the cases environment in a table with alternating row colours. Here is some example code.

\usepackage[table]{xcolor}
\usepackage{amsmath}

\begin{document}
    \rowcolors{2}{gray!25}{white}
    \begin{tabular}{cc}
        1 & 7\\
        2 & \(\displaystyle
            \begin{cases}
                a & \quad b\\
                c & \quad d
            \end{cases}\)\\
        3 & 4
        \end{tabular}
\end{document}

Unfortunately, this results in the braces being overlapped by white. How can I fix this?

Answer 1

See if the following solution fulfill your expectation:

\documentclass[12pt]{article}
\usepackage[table]{xcolor}  %to use direct sum symbol
\usepackage{mathtools}              % <---
\usepackage{cellspace}              % <---
\setlength\cellspacetoplimit{3pt}   % <---
\setlength\cellspacebottomlimit{3pt}% <---

\begin{document}
    \begin{center}
\rowcolors{2}{gray!25}{white}
    \begin{tabular}{cSc}
        1 & 7               \\ 
        2 & \(
            \begin{dcases}   % <---
                a & \quad b\\
                c & \quad d
            \end{dcases}\)  \\ 
        3 & 4
        \end{tabular}
    \end{center}
\end{document}