/ ____________\ / ____________\
| ___ / ___ | | ___ / ___ |
|\/ 2 *\/ -1 + \/ 5 | |\/ 2 *\/ -1 + \/ 5 |
(atan|---------------------|, pi - atan|---------------------|)
\ 2 / \ 2 /
$$x\ in\ \left(\operatorname{atan}{\left(\frac{\sqrt{2} \sqrt{-1 + \sqrt{5}}}{2} \right)}, \pi - \operatorname{atan}{\left(\frac{\sqrt{2} \sqrt{-1 + \sqrt{5}}}{2} \right)}\right)$$
x in Interval.open(atan(sqrt(2)*sqrt(-1 + sqrt(5))/2), pi - atan(sqrt(2)*sqrt(-1 + sqrt(5))/2))
/ / ____________\ / ____________\ \
| | ___ / ___ | | ___ / ___ | |
| |\/ 2 *\/ -1 + \/ 5 | |\/ 2 *\/ -1 + \/ 5 | |
And|x < pi - atan|---------------------|, atan|---------------------| < x|
\ \ 2 / \ 2 / /
$$x < \pi - \operatorname{atan}{\left(\frac{\sqrt{2} \sqrt{-1 + \sqrt{5}}}{2} \right)} \wedge \operatorname{atan}{\left(\frac{\sqrt{2} \sqrt{-1 + \sqrt{5}}}{2} \right)} < x$$
(atan(sqrt(2)*sqrt(-1 + sqrt(5))/2) < x)∧(x < pi - atan(sqrt(2)*sqrt(-1 + sqrt(5))/2))