\documentclass[12pt]{article} \usepackage[total={6.25in,10in},left=1.25in,top=0.5in,includehead,includefoot]{geometry} \usepackage{mathtools} \newcommand*{\1}{\hspace{1pt}} \newcommand*{\tsqrt}[1]{{\textstyle{\sqrt{#1}}}} \begin{document} Test : \begin{flalign} \mathrlap{\text{if $4 \, \omega_0^2 > \gamma^2$ :}} && \lambda &= \frac{1}{2} \1 \tsqrt{\displaystyle{4 \, \omega_0^2 - \gamma^2}}, & \\[12pt] \mathrlap{\text{if $4 \, \omega_0^2 < \gamma^2$ :}} && \kappa &= \frac{1}{2} \1 \tsqrt{\displaystyle{\gamma^2 - 4 \, \omega_0^2}}. & \end{flalign} \begin{equation} EQUATION \end{equation} \end{document}
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As you can see, the equations aren't well centered above the "EQUATION" below them. I need them to be well balanced (i.e. centered). What am I doing wrong here?