Solve cos(60°)

Step-by-step solution

1. $60°$ is one of the standard "special angles" worth memorising.

2. In radians: $60° = \frac{\pi}{3}$.

3. On the unit circle, the point at $60°$ has coordinates $\bigl(\frac{1}{2}, \frac{\sqrt{3}}{2}\bigr)$.

4. Cosine is the x-coordinate: $\cos(60°) = \frac{1}{2}$.

5. Geometric verification: in a $30°$-$60°$-$90°$ triangle, the side adjacent to the $60°$ angle is half the hypotenuse — confirming $\cos 60° = \tfrac{1}{2}$.