\[\boxed{\mathbf{641.}ОК\ ГДЗ\ –\ домашка\ на\ 5}\]
\[\overrightarrow{a}(5; - 1;2):\]
\[\overrightarrow{a} = 5\overrightarrow{i} - \overrightarrow{j} + 2\overrightarrow{k}\text{.\ \ \ }\]
\[\overrightarrow{b}( - 3; - 1;0):\]
\[\overrightarrow{b} = - 3\overrightarrow{i} - \overrightarrow{j}.\]
\[\overrightarrow{c}(0; - 1;0):\]
\[\overrightarrow{c} = - \overrightarrow{j}.\]
\[\overrightarrow{d}(0;0;0):\]
\[\overrightarrow{d} = \overrightarrow{0}.\]