SA Geometry

Find the angle between the vectors $\overrightarrow{u}$   =(3,3, $\sqrt{2}$  ) and  $\overrightarrow{v}$  =(2,2, $-\sqrt{2}$  )

In the adjacent figure, B1D=5, B1C1= $\frac{5\sqrt{3}}{2}$  . Find the angle between B1D and DD1C1C

 Given the points A(-4,3,2) and B(0,5,-8). Find the coordinates of  $\overrightarrow{AB}$  and it’s length.

In the triangle ABC the vertices are: A(-2,1,3) ; B(-1,1,3) ; C(-2,2,3). Find the area of the triangle ABC

The vectors $\overrightarrow{u}=\left(4,a,-6\right)$   And  $\overrightarrow{v\ =\left(b,-1,3\right)}$  Are parallel. Find a+b