If two vectors be such that , then the angle between them is
π/4
π/3
π/2
None of these
0
-1
1
2
3
2/3
-2/3
-3/2
3/2
If θ is the angle between two unit vectors , then cos θ is equal to
If cross product of two non - zero vectors is zero, then the vectors are
Collinear
Co - directional
Co - initial
Co - terminus