A good answer might be:

The picture is at right.

The dot product is ( 0.6, 0.8 )  ·  ( 0.8, 0.6 ) = 
0.6*0.8 + 0.8*0.6 = 0.48 + 0.48  =  0.96
The angle is arc cos( 0.96 )  =  16.26°

 


Non-unit Vectors

 

Consider the following problem: Find the angle between the two vectors:

j  =  (3, 4)T  ,     k  =  (0, 2)T

These are not unit vectors, so you can not find the angle between them without further work. As always, draw a sketch first.

QUESTION 14:

What do you suggest doing, so that the angle between the two vectors can be found?