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\begin{document}

  $ x=r*sin(\vartheta)*cos({\phi})

$   y=r*sin({\vartheta})*sin({\phi})

 $  z=r*cos({\vartheta})

  $ {\vartheta}=0 \div \pi

$   {\phi}=0 \div 2*\pi.$$

\end{document}
