What is the angle between <4,2,1> and <8,0,0>?

1 Answer
Mar 2, 2017

The angle is =29.2º

Explanation:

The angle between A and B is given by the dot product definition.

A.B=ABcosθ

Where θ is the angle between A and B

The dot product is

A.B=4,2,1.8,0,0=32

The modulus of A= 4,2,1=16+4+1=21

The modulus of B= 8,0,0=64=8

So,

cosθ=A.BAB=32218=0.87

θ=29.2º