Question: Find the angle between the vectors A = (1, 2, 2) and B = (2, 0, 2).
Options:
Correct Answer: 60°
Solution:
cos(θ) = (A · B) / (|A| |B|). A · B = 1*2 + 2*0 + 2*2 = 6. |A| = √(1^2 + 2^2 + 2^2) = 3, |B| = √(2^2 + 0^2 + 2^2) = 2√2. cos(θ) = 6 / (3 * 2√2) = 1/√2, θ = 45°.