What is the value of cos(2x) if cos(x) = 1 / √2?
Question 1
Q1. What is the value of cos(2x) if cos(x) = 1 / √2?
Answer: 0
Explanation: Using cos(2x) = 2cos²(x) - 1, we find cos(2x) = 2 * (1 / 2) - 1 = 0.