What is the angle between <2,3,1> and <8,3,5>?

1 Answer
Feb 29, 2016

cosθ=<2,3,1><8,3,5>(22+(32)+(1)2)((8)2+32+(5)2)
=2(8)+(3)(3)+(1)(5)(1498)
=201372
θ=cos1(201372)=122.68

Explanation:

To find theta take the inverse cosine of the dot product of the given vectors divided by the product of the magnitude of each of the vectors.