Answer:
30° or π/6 rad
Explanation:
Imagine or draw a right triangle with horizontal side (√3)/2 and vertical side 1/2. Verify that the hypotenuse of this triangle is 1 (which it must be, since the circle is a unit circle): [(√3)/2)^2 + (1/2)^2 = r^2, which leads to r = 1.
The tangent function tan x = opp/adj takes on the following values here:
tan x = 1/2 over √(3/2)/2, or 1/√3. Using a calculator or a table of trig function values, we find that the angle x is π/6 radians, or 30°