Question

The angle between two vectors a = i+2j-k and b=2i+j+k is

Answer 1

Here is the solution:

Given vectors are a = i+2j-k and b=2i+j+k

We have to find angle between given vectors

A.b= |a|.|b|cosθ

a.b= 2+2-1= 3

|a|= root 6

|b|= root 6

Therefore by using the formula  

cos θ = 3/6

cos θ  = 1/2

θ = 30

Therefore, answer The angle between two vectors a = i+2j-k and b=2i+j+k is 30.

Answer 2

Answer:

cos theta = 60

Step-by-step explanation:

as cos  60 equals to 1/2