If and are unit vectors, then what is the angle between and for to be a unit vector?[CBSE 2016]

Question

If  and  are unit vectors, then what is the angle between  and  for  to be a unit vector?[CBSE 2016]

Philoid · Accepted Answer

Given:

For  to be a unit vector, its magnitude is equal to 1

Formula:

2 = 2&radic;2 cos&theta;