2 Find a unit vector perpendicular to each of the vector 
and
a
b
a
b
+
−
r
r
r
r
, where
ˆ
ˆ
ˆ
ˆ
ˆ
ˆ
3
2
2
and
2
2
a
i
j
k
b
i
j
k
=
+
+
= +
−
r
r 3 If a unit vector ar  makes angles 
ˆ
ˆ
with ,
with
3
i4
j
π
π
 and an acute angle θ with
ˆk , then find θ and hence, the components of ar