Vector Dot Product Concepts

What type of quantity is the result of a vector dot product?

• A vector

• A scalar

• A matrix

• A cross product

Given vector A = <3, -1> and vector B = <2, 5>, what is A • B?

• <6, -5>

• 1

• -1

• <5, 4>

Which of the following properties is true for the vector dot product?

• A • B = B • A

• A • (B + C) = (A • B) + C

• (cA) • B = c + (A • B)

• A • A = |A|

How can the cosine of the angle (θ) between two vectors A and B be calculated using their dot product and magnitudes?

• cos θ = (A • B) / (|A| + |B|)

• cos θ = (|A| • |B|) / (A • B)

• cos θ = (A • B) / (|A| |B|)

• cos θ = (|A| + |B|) / (A • B)

If two vectors are orthogonal, what is the value of their dot product?

• 1

• -1

• 0

• Undefined