El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\cos{\left(x - \frac{\pi}{6} \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - \frac{\pi}{3}$$
$$x_{2} = \frac{2 \pi}{3}$$
Solución numérica$$x_{1} = -4939.63084899435$$
$$x_{2} = 30.3687289847013$$
$$x_{3} = 20.943951023932$$
$$x_{4} = -85.870199198121$$
$$x_{5} = 36.6519142918809$$
$$x_{6} = -92.1533845053006$$
$$x_{7} = 55.5014702134197$$
$$x_{8} = 64.9262481741891$$
$$x_{9} = -79.5870138909414$$
$$x_{10} = -54.4542726622231$$
$$x_{11} = 74.3510261349584$$
$$x_{12} = -29.3215314335047$$
$$x_{13} = -51.3126800086333$$
$$x_{14} = -45.0294947014537$$
$$x_{15} = 52.3598775598299$$
$$x_{16} = 99.4837673636768$$
$$x_{17} = 77.4926187885482$$
$$x_{18} = -19.8967534727354$$
$$x_{19} = -154.985237577096$$
$$x_{20} = -13.6135681655558$$
$$x_{21} = 61.7846555205993$$
$$x_{22} = 11.5191730631626$$
$$x_{23} = 93.2005820564972$$
$$x_{24} = 33.5103216382911$$
$$x_{25} = 27.2271363311115$$
$$x_{26} = 80.634211442138$$
$$x_{27} = 14.6607657167524$$
$$x_{28} = -67.0206432765823$$
$$x_{29} = -38.7463093942741$$
$$x_{30} = -76.4454212373516$$
$$x_{31} = 39.7935069454707$$
$$x_{32} = -95.2949771588904$$
$$x_{33} = -23.0383461263252$$
$$x_{34} = -57.5958653158129$$
$$x_{35} = 24.0855436775217$$
$$x_{36} = 5.23598775598299$$
$$x_{37} = -32.4631240870945$$
$$x_{38} = -63.8790506229925$$
$$x_{39} = -26.1799387799149$$
$$x_{40} = -70.162235930172$$
$$x_{41} = -60.7374579694027$$
$$x_{42} = -16.7551608191456$$
$$x_{43} = 58.6430628670095$$
$$x_{44} = -10.471975511966$$
$$x_{45} = 46.0766922526503$$
$$x_{46} = -48.1710873550435$$
$$x_{47} = -98.4365698124802$$
$$x_{48} = -73.3038285837618$$
$$x_{49} = -4.18879020478639$$
$$x_{50} = 2.0943951023932$$
$$x_{51} = 17.8023583703422$$
$$x_{52} = 102.625360017267$$
$$x_{53} = -7.33038285837618$$
$$x_{54} = 49.2182849062401$$
$$x_{55} = -89.0117918517108$$
$$x_{56} = 8.37758040957278$$
$$x_{57} = 83.7758040957278$$
$$x_{58} = 96.342174710087$$
$$x_{59} = -1.0471975511966$$
$$x_{60} = 71.2094334813686$$
$$x_{61} = 68.0678408277789$$
$$x_{62} = -35.6047167406843$$
$$x_{63} = 86.9173967493176$$
$$x_{64} = 90.0589894029074$$
$$x_{65} = -41.8879020478639$$
$$x_{66} = -82.7286065445312$$
$$x_{67} = 42.9350995990605$$