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                      i \sin\left(#1\right)}
\newcommand{\ccis}[1]{\hbox{\rm cis}^*\left(#1\right)}
\newcommand{\ccisl}[1]{\cos\left(#1\right) - 
                       i \sin\left(#1\right)}
\newcommand{\cas}[1]{\hbox{\rm cas}\left(#1\right)}
\newcommand{\casl}[1]{\cos\left(#1\right) + \sin\left(#1\right)}
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\newcommand{\shah}{{\rm I \! I \! I}}
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                                    ^{\frac{#2_2}{2}}}
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