/ / / ____\\ / / ____\\ \
| | |\/ 15 || |pi |\/ 15 || /3*pi \|
Or|And|0 <= x, x <= atan|------||, And|-- <= x, x <= pi - atan|------||, And|---- <= x, x <= 2*pi||
\ \ \ 15 // \2 \ 15 // \ 2 //
$$\left(0 \leq x \wedge x \leq \operatorname{atan}{\left(\frac{\sqrt{15}}{15} \right)}\right) \vee \left(\frac{\pi}{2} \leq x \wedge x \leq \pi - \operatorname{atan}{\left(\frac{\sqrt{15}}{15} \right)}\right) \vee \left(\frac{3 \pi}{2} \leq x \wedge x \leq 2 \pi\right)$$
((3*pi/2 <= x)∧(x <= 2*pi))∨((0 <= x)∧(x <= atan(sqrt(15)/15)))∨((pi/2 <= x)∧(x <= pi - atan(sqrt(15)/15)))
/ ____\ / ____\
|\/ 15 | pi |\/ 15 | 3*pi
[0, atan|------|] U [--, pi - atan|------|] U [----, 2*pi]
\ 15 / 2 \ 15 / 2
$$x\ in\ \left[0, \operatorname{atan}{\left(\frac{\sqrt{15}}{15} \right)}\right] \cup \left[\frac{\pi}{2}, \pi - \operatorname{atan}{\left(\frac{\sqrt{15}}{15} \right)}\right] \cup \left[\frac{3 \pi}{2}, 2 \pi\right]$$
x in Union(Interval(0, atan(sqrt(15)/15)), Interval(pi/2, pi - atan(sqrt(15)/15)), Interval(3*pi/2, 2*pi))