Formula_12350

\[\left.\begin{array}{l}\sum F_{k x}=0, \quad \sum F_{k y}=0, \quad \sum F_{k z}=0 \\\sum m_{x}\left(F_{k}\right)=0, \quad \sum m_{y}\left(F_{k}\right)=0, \quad \sum m_{z}\left(F_{k}\right)=0 .\end{array}\right\}\]