Задание 
Определи угол между векторами, расположенными в кубе.
\(\widehat{\left(\overrightarrow{A_1D_1} \,\overrightarrow{BC}\right)}=\) 0\(\degree\);
\(\(\widehat{\left(\overrightarrow{AC} \, \overrightarrow{C_1A_1}\right)}\)=) 180\(\degree\);
\(\widehat{\left( {\overrightarrow{AC}} {\overrightarrow{BC}} \right)} =\) 45\(\degree\);
\(\widehat{\left({\overrightarrow{DA} \,\overrightarrow{B_1D_1}}\right)}=\) 135\(\degree\).