El gráfico de la función cruce el eje T con f = 0
o sea hay que resolver la ecuación:
$$2 \cos^{3}{\left(t \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje T:
Solución analítica$$t_{1} = \frac{\pi}{2}$$
$$t_{2} = \frac{3 \pi}{2}$$
Solución numérica$$t_{1} = 36.128317789764$$
$$t_{2} = -20.4203505482106$$
$$t_{3} = 58.1194603256925$$
$$t_{4} = -45.5531401844306$$
$$t_{5} = -95.8185603030962$$
$$t_{6} = 92.6770059000324$$
$$t_{7} = -14.1371260033657$$
$$t_{8} = 70.6858302611407$$
$$t_{9} = 64.4026122770508$$
$$t_{10} = 26.7034598912501$$
$$t_{11} = 23.5619763533234$$
$$t_{12} = 51.8363261592826$$
$$t_{13} = -23.5619897288019$$
$$t_{14} = 20.4203112367381$$
$$t_{15} = -1.57083925518957$$
$$t_{16} = 48.6946439323886$$
$$t_{17} = 1.57080273224359$$
$$t_{18} = -7.85396939058216$$
$$t_{19} = 14.1371748405436$$
$$t_{20} = 73.8274768053124$$
$$t_{21} = -67.5442906223714$$
$$t_{22} = 29.8451754771722$$
$$t_{23} = 42.4114617473496$$
$$t_{24} = -51.8362625267018$$
$$t_{25} = 80.1106035284868$$
$$t_{26} = -89.5354410428862$$
$$t_{27} = -73.827410994311$$
$$t_{28} = -42.4114638604687$$
$$t_{29} = 45.5531567451367$$
$$t_{30} = -58.1194276545353$$
$$t_{31} = 7.85402475701276$$
$$t_{32} = -29.8451152214988$$
$$t_{33} = -36.1282768063468$$
$$t_{34} = 95.818627417042$$
$$t_{35} = -80.1105785507599$$
$$t_{36} = 86.3937628262857$$