Question 1043597
Triangle that is 1-sqrt3-2 has a tangent that is 1/sqrt(3), and that is sqrt(3)/3
That triangle is a 30-60-90 triangle, so the tangent that gives that value is 30 degrees or pi/6 radians.
It also occurs when the sine and cosine are negative (tangent=sin/cos), and that would be at 210 degrees or 7pi/6 radians.
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cos^2 theta=1/4
cos theta= +/- 1/2
That occurs at pi/6, pi/3, 2pi/3, and 5pi/3.  Notice that -1/2 is a solution, so there are twice as many instances.
30-120-240-300 degrees.