Graph of the function intersects the axis X at f = 0
so we need to solve the equation:
$$4 \sin{\left(x + \frac{\pi}{6} \right)} + 2 = 0$$
Solve this equationThe points of intersection with the axis X:
Analytical solution$$x_{1} = - \frac{\pi}{3}$$
$$x_{2} = \pi$$
Numerical solution$$x_{1} = -97.3893722612836$$
$$x_{2} = -70.162235930172$$
$$x_{3} = -72.2566310325652$$
$$x_{4} = -59.6902604182061$$
$$x_{5} = -78.5398163397448$$
$$x_{6} = 97.3893722612836$$
$$x_{7} = 9.42477796076938$$
$$x_{8} = 99.4837673636768$$
$$x_{9} = 86.9173967493176$$
$$x_{10} = -57.5958653158129$$
$$x_{11} = -32.4631240870945$$
$$x_{12} = 84.8230016469244$$
$$x_{13} = 5.23598775598299$$
$$x_{14} = -21.9911485751286$$
$$x_{15} = 3.14159265358979$$
$$x_{16} = -95.2949771588904$$
$$x_{17} = 36.6519142918809$$
$$x_{18} = -220.958683302482$$
$$x_{19} = 28.2743338823081$$
$$x_{20} = 68.0678408277789$$
$$x_{21} = -13.6135681655558$$
$$x_{22} = -28.2743338823081$$
$$x_{23} = -40.8407044966673$$
$$x_{24} = -65.9734457253857$$
$$x_{25} = -91.106186954104$$
$$x_{26} = 42.9350995990605$$
$$x_{27} = -76.4454212373516$$
$$x_{28} = 17.8023583703422$$
$$x_{29} = 80.634211442138$$
$$x_{30} = 55.5014702134197$$
$$x_{31} = 30.3687289847013$$
$$x_{32} = 40.8407044966673$$
$$x_{33} = -89.0117918517108$$
$$x_{34} = 49.2182849062401$$
$$x_{35} = -53.4070751110265$$
$$x_{36} = -3.14159265358979$$
$$x_{37} = -7.33038285837618$$
$$x_{38} = 21.9911485751286$$
$$x_{39} = -84.8230016469244$$
$$x_{40} = 34.5575191894877$$
$$x_{41} = -45.0294947014537$$
$$x_{42} = -9.42477796076938$$
$$x_{43} = -15.707963267949$$
$$x_{44} = 47.1238898038469$$
$$x_{45} = 93.2005820564972$$
$$x_{46} = 53.4070751110265$$
$$x_{47} = 74.3510261349584$$
$$x_{48} = 24.0855436775217$$
$$x_{49} = 61.7846555205993$$
$$x_{50} = 65.9734457253857$$
$$x_{51} = 91.106186954104$$
$$x_{52} = 11.5191730631626$$
$$x_{53} = 59.6902604182061$$
$$x_{54} = -82.7286065445312$$
$$x_{55} = -26.1799387799149$$
$$x_{56} = -63.8790506229925$$
$$x_{57} = -1.0471975511966$$
$$x_{58} = 78.5398163397448$$
$$x_{59} = 15.707963267949$$
$$x_{60} = 72.2566310325652$$
$$x_{61} = -19.8967534727354$$
$$x_{62} = -47.1238898038469$$
$$x_{63} = -103.672557568463$$
$$x_{64} = -38.7463093942741$$
$$x_{65} = -51.3126800086333$$
$$x_{66} = -34.5575191894877$$