Space vector

Exercise1.1

1.
For $\boldsymbol{A} = -\boldsymbol{i} + 2\:\boldsymbol{j} + 3\:\boldsymbol{k}, \boldsymbol{B} = -3\:\boldsymbol{j} + 2\:\boldsymbol{k}$, find the followings:D

(1)
$2\boldsymbol{A}$
(2)
$3\boldsymbol{B} - 2\boldsymbol{A}$
(3)
$\vert\boldsymbol{A}\vert$
(4)
$\vert\boldsymbol{A} + \boldsymbol{B}\vert$

2.
For the vectors $\boldsymbol{A} = -\boldsymbol{i} + 2\:\boldsymbol{j} + 3\:\boldsymbol{k}$ and $\boldsymbol{B} = -\:\boldsymbol{i} + 2\:\boldsymbol{j} + \:\boldsymbol{k}$, find the followings:

(1)
$\boldsymbol{A}$ + $\boldsymbol{B}$

(2)
Angle between $\boldsymbol{A}$ and $\boldsymbol{B}$