Question

If A bar and B bar are parallel then A bar times B bar

Answer 1

Explanation:

1. Dot Product

We know that by definition of dot product of two vector

⃗A.⃗B = |⃗A||⃗B|cos(θ)

Since the given vectors are parallel θ = 0

⇒ ⃗A.⃗B = |⃗A||⃗B|cos(0) = |⃗A||⃗B|*1

⇒ ⃗A.⃗B = |⃗A||⃗B|

2. Cross Product

We know that by definition of cross product of two vector

⃗Ax⃗B = |⃗A||⃗B|sin(θ)

Since the given vectors are parallel θ = 0

⇒ ⃗Ax⃗B = |⃗A||⃗B|sin(0) = |⃗A||⃗B|*0

⇒ ⃗Ax⃗B = 0