EXERCISE 3 2
1 Let 
2
4
1
3
2
5
A
, B
, C
3
2
2
5
3
4
−






=
=
=






−






Find each of the following:
(i) A + B
(ii) A – B
(iii) 3A – C
(iv) AB
(v) BA
2 Compute the following:
(i)
a
b
a
b
b
a
b
a




+




−



(ii)
2
2
2
2
2
2
2
2
2
2
2
2
a
b
b
c
ab
bc
ac
ab
a
c
a
b


+
+


+




−
−
+
+






(iii)
1
4
6
12
7
6
8
5
16
8
0
5
2
8
5
3
2
4
−
−








+












(iv)
2
2
2
2
2
2
2
2
cos
sin
sin
cos
sin
cos
cos
sin
x
x
x
x
x
x
x
x




+












3