El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$2 \frac{\sqrt{3}}{3} \cos{\left(x \right)} \sin{\left(x \right)} - \cos{\left(x \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - \frac{\pi}{2}$$
$$x_{2} = \frac{\pi}{3}$$
$$x_{3} = \frac{\pi}{2}$$
$$x_{4} = \frac{2 \pi}{3}$$
Solución numérica$$x_{1} = 48.6946861306418$$
$$x_{2} = 38.7463093942741$$
$$x_{3} = 32.4631240870945$$
$$x_{4} = -54.4542726622231$$
$$x_{5} = -14.1371669411541$$
$$x_{6} = -4.18879020478639$$
$$x_{7} = 90.0589894029074$$
$$x_{8} = -74.3510261349584$$
$$x_{9} = 76.4454212373516$$
$$x_{10} = -1.5707963267949$$
$$x_{11} = 23.5619449019235$$
$$x_{12} = 73.8274273593601$$
$$x_{13} = 95.2949771588904$$
$$x_{14} = 89.0117918517108$$
$$x_{15} = 4.71238898038469$$
$$x_{16} = 8.37758040957278$$
$$x_{17} = -20.4203522483337$$
$$x_{18} = -26.7035375555132$$
$$x_{19} = -42.9350995990605$$
$$x_{20} = 252.898208613978$$
$$x_{21} = -95.8185759344887$$
$$x_{22} = 51.3126800086333$$
$$x_{23} = -30.3687289847013$$
$$x_{24} = 20.4203522483337$$
$$x_{25} = 46.0766922526503$$
$$x_{26} = 67.5442420521806$$
$$x_{27} = 36.1283155162826$$
$$x_{28} = 58.1194640914112$$
$$x_{29} = -29.845130209103$$
$$x_{30} = -41.8879020478639$$
$$x_{31} = -92.1533845053006$$
$$x_{32} = -23.0383461263252$$
$$x_{33} = -29.3215314335047$$
$$x_{34} = 77.4926187885482$$
$$x_{35} = -16.7551608191456$$
$$x_{36} = 39.7935069454707$$
$$x_{37} = 7.33038285837618$$
$$x_{38} = -99.4837673636768$$
$$x_{39} = 58.6430628670095$$
$$x_{40} = 33.5103216382911$$
$$x_{41} = -49.2182849062401$$
$$x_{42} = 83.7758040957278$$
$$x_{43} = 51.8362787842316$$
$$x_{44} = 82.7286065445312$$
$$x_{45} = 80.1106126665397$$
$$x_{46} = -48.1710873550435$$
$$x_{47} = 64.9262481741891$$
$$x_{48} = 14.1371669411541$$
$$x_{49} = -80.634211442138$$
$$x_{50} = -85.870199198121$$
$$x_{51} = -86.9173967493176$$
$$x_{52} = 20.943951023932$$
$$x_{53} = 42.4115008234622$$
$$x_{54} = -61.7846555205993$$
$$x_{55} = -45.553093477052$$
$$x_{56} = -60.7374579694027$$
$$x_{57} = -11.5191730631626$$
$$x_{58} = -58.1194640914112$$
$$x_{59} = 45.0294947014537$$
$$x_{60} = 26.1799387799149$$
$$x_{61} = -93.2005820564972$$
$$x_{62} = 71.2094334813686$$
$$x_{63} = 96.342174710087$$
$$x_{64} = -83.2522053201295$$
$$x_{65} = -68.0678408277789$$
$$x_{66} = -70.6858347057703$$
$$x_{67} = 27.2271363311115$$
$$x_{68} = -39.2699081698724$$
$$x_{69} = -36.1283155162826$$
$$x_{70} = -64.4026493985908$$
$$x_{71} = 70.162235930172$$
$$x_{72} = 92.6769832808989$$
$$x_{73} = -17.8023583703422$$
$$x_{74} = -51.8362787842316$$
$$x_{75} = 2.0943951023932$$
$$x_{76} = 1.0471975511966$$
$$x_{77} = -5.23598775598299$$
$$x_{78} = 13.6135681655558$$
$$x_{79} = -89.5353906273091$$
$$x_{80} = 102.101761241668$$
$$x_{81} = -55.5014702134197$$
$$x_{82} = -10.471975511966$$
$$x_{83} = -73.8274273593601$$
$$x_{84} = 29.845130209103$$
$$x_{85} = 14.6607657167524$$
$$x_{86} = -36.6519142918809$$
$$x_{87} = 202.109127380943$$
$$x_{88} = -98.4365698124802$$
$$x_{89} = 86.3937979737193$$
$$x_{90} = 64.4026493985908$$
$$x_{91} = -67.0206432765823$$
$$x_{92} = -80.1106126665397$$
$$x_{93} = -7.85398163397448$$