State a geometrical relationship between the answer to part (a)(i) and the vectors \(\left( \begin{array} { c } 1 2 - 1 \end{array} \right)\) and \(\left( \begin{array} { c } 3 5 - 2 \end{array} \right)\).
Verify the relationship stated in part (a)(ii).
Find the angle between the vectors \(2 \mathbf { i } - 2 \mathbf { j } + \mathbf { k }\) and \(4 \mathbf { i } - \mathbf { j } + 8 \mathbf { k }\).