Given vectors \(\vec{a} = (-1;2;1)\),
\(\vec{b} = (0;-1;1)\), and
\(\vec{c} = (-2;0;1)\), find the length
of the vector \(\vec{u} =\vec{ a} - 2\vec{b} + \vec{c}\).
We are given points \( A = [2;1] \), \( B = [7;2] \), and \( T = [4;3] \), where point \( T \) is the centroid of triangle \( ABC \). Find the coordinates of \( C \), which is the vertex of \( ABC \).
Given the vectors \( \overrightarrow{a} \), \( \overrightarrow{b} \), and \( \overrightarrow{c} \) shown in the picture, express the vector \( \overrightarrow{c} \) as a linear combination of vectors \( \overrightarrow{a} \) and \( \overrightarrow{b} \).
The picture shows a rectangular cuboid \( ABCDEFGH \). In the cuboid find the vector that is the sum of \( \overrightarrow{AB} + \overrightarrow{AH} + \overrightarrow{EG} + \overrightarrow{FA} + \overrightarrow{HE} \).