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\begin{document}
eqnarray �Ķ��� lefteqn �μ��ιԤ�û�����ˡ�svg �� 1 ���ܤ��ڤ��
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\begin{eqnarray}
  \lefteqn{%
    123456789|123456789|123456789|123456789|123456789|123456789|123456789|
  }
  \\&=&
  123456789|123456789|
\end{eqnarray}
eqnarray$\ast$ ���Ȥ���ʴ�����
\begin{eqnarray*}
  \lefteqn{%
    123456789|123456789|123456789|123456789|123456789|123456789|123456789|
  }
  \\&=&
  123456789|123456789|
\end{eqnarray*}
\end{document}
