strange formatting

[Artemio González López]

I’ve been having some problems with auctex formatting of some equations. Here’s a minimal example:

\documentclass[a4paper,11pt]{article}

\usepackage{babel}

\usepackage{amsmath}

\begin{document}

\[

  I_O=Ml^2\begin{pmatrix}

            \frac1{12}& 0& 0\\[2pt]

            0& \frac1{12}& 0\\[2pt]

            0& 0& \frac16

          \end{pmatrix}+Ml^2

          \begin{pmatrix}

            \hfill\frac14& -\frac14& 0\\[2pt]

            -\frac14& \hfill\frac14& 0\\[2pt]

            \hfill 0& \hfill 0& \frac12

          \end{pmatrix}=Ml^2

          \begin{pmatrix}

            \hfill\frac13& -\frac14& 0\\[2pt]

            -\frac14& \hfill\frac13& 0\\[2pt]

            \hfill0& \hfill0& \frac23

          \end{pmatrix}

        \]

        

      \end{document}

After the equation all text is aligned with the closing \[, which is a pain. Is this reproducible? And, more importantly, how could I fix it?

Thanks in advance,

Artemio

Artemio Gonzalez Lopez
artemiog@mac.com

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