Graph of the function intersects the axis X at f = 0
so we need to solve the equation:
$$2 \cot{\left(\frac{x}{2} - \frac{\pi}{6} \right)} = 0$$
Solve this equationThe points of intersection with the axis X:
Analytical solution$$x_{1} = - \frac{2 \pi}{3}$$
Numerical solution$$x_{1} = 60.7374579694027$$
$$x_{2} = 4.18879020478639$$
$$x_{3} = -14.6607657167524$$
$$x_{4} = 92.1533845053006$$
$$x_{5} = 29.3215314335047$$
$$x_{6} = -102.625360017267$$
$$x_{7} = -2.0943951023932$$
$$x_{8} = -83.7758040957278$$
$$x_{9} = -71.2094334813686$$
$$x_{10} = -96.342174710087$$
$$x_{11} = 41.8879020478639$$
$$x_{12} = -33.5103216382911$$
$$x_{13} = -27.2271363311115$$
$$x_{14} = -77.4926187885482$$
$$x_{15} = -64.9262481741891$$
$$x_{16} = -90.0589894029074$$
$$x_{17} = 67.0206432765823$$
$$x_{18} = 48.1710873550435$$
$$x_{19} = 85.870199198121$$
$$x_{20} = -46.0766922526503$$
$$x_{21} = 23.0383461263252$$
$$x_{22} = 16.7551608191456$$
$$x_{23} = -39.7935069454707$$
$$x_{24} = -52.3598775598299$$
$$x_{25} = -58.6430628670095$$
$$x_{26} = 10.471975511966$$
$$x_{27} = 98.4365698124802$$
$$x_{28} = -8.37758040957278$$
$$x_{29} = 79.5870138909414$$
$$x_{30} = 73.3038285837618$$
$$x_{31} = 35.6047167406843$$
$$x_{32} = 54.4542726622231$$
$$x_{33} = -20.943951023932$$