Question: If vector A = 5i + 5j and vector B = 5i - 5j, what is the angle between A and B?
Options:
Correct Answer: 90 degrees
Solution:
cos(θ) = (A · B) / (|A||B|) = (25 - 25) / (√(50) * √(50)) = 0, θ = 90 degrees.