El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\cos{\left(2 x \right)} - \frac{\sqrt{3}}{2} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = \frac{\pi}{12}$$
$$x_{2} = \frac{11 \pi}{12}$$
Solución numérica$$x_{1} = -103.934356956262$$
$$x_{2} = 50.0036830696375$$
$$x_{3} = -93.9859802198946$$
$$x_{4} = 31.6777259236971$$
$$x_{5} = 9.68657734856853$$
$$x_{6} = -15.9697626557481$$
$$x_{7} = 62.5700536839967$$
$$x_{8} = -40.5789051088682$$
$$x_{9} = -28.012534494509$$
$$x_{10} = 68.8532389911763$$
$$x_{11} = -18.5877565337396$$
$$x_{12} = -6.02138591938044$$
$$x_{13} = 12.30457122656$$
$$x_{14} = 24.8709418409192$$
$$x_{15} = 71.9948316447661$$
$$x_{16} = -53.6688744988256$$
$$x_{17} = 81.9432083811338$$
$$x_{18} = -232.739655753444$$
$$x_{19} = -56.2868683768171$$
$$x_{20} = -100.269165527074$$
$$x_{21} = 34.2957198016886$$
$$x_{22} = -663.137849295245$$
$$x_{23} = 2.87979326579064$$
$$x_{24} = -87.7027949127151$$
$$x_{25} = -78.2780169519457$$
$$x_{26} = -19.1113553093379$$
$$x_{27} = 97.6511716490827$$
$$x_{28} = -81.9432083811338$$
$$x_{29} = 100.269165527074$$
$$x_{30} = 59.9520598060052$$
$$x_{31} = 53.6688744988256$$
$$x_{32} = 44.2440965380563$$
$$x_{33} = -85.0848010347236$$
$$x_{34} = 18.5877565337396$$
$$x_{35} = 132.20869083857$$
$$x_{36} = 93.9859802198946$$
$$x_{37} = -59.9520598060052$$
$$x_{38} = -47.3856891916461$$
$$x_{39} = 6.02138591938044$$
$$x_{40} = 15.9697626557481$$
$$x_{41} = 90.8443875663049$$
$$x_{42} = -97.6511716490827$$
$$x_{43} = -21.7293491873294$$
$$x_{44} = 69.3768377667746$$
$$x_{45} = 46.8620904160477$$
$$x_{46} = 22.2529479629277$$
$$x_{47} = 66.2352451131848$$
$$x_{48} = 25.3945406165175$$
$$x_{49} = -62.5700536839967$$
$$x_{50} = 40.5789051088682$$
$$x_{51} = 84.5612022591253$$
$$x_{52} = -65.7116463375865$$
$$x_{53} = -75.6600230739542$$
$$x_{54} = -34.2957198016886$$
$$x_{55} = 56.2868683768171$$
$$x_{56} = 91.3679863419031$$
$$x_{57} = -71.9948316447661$$
$$x_{58} = -9.68657734856853$$
$$x_{59} = 47.3856891916461$$
$$x_{60} = -84.5612022591253$$
$$x_{61} = -3.40339204138894$$
$$x_{62} = -41.1025038844665$$
$$x_{63} = -12.30457122656$$
$$x_{64} = -25.3945406165175$$
$$x_{65} = -69.3768377667746$$
$$x_{66} = -63.093652459595$$
$$x_{67} = 75.6600230739542$$
$$x_{68} = -31.6777259236971$$
$$x_{69} = 78.2780169519457$$
$$x_{70} = -43.720497762458$$
$$x_{71} = -37.9609112308767$$
$$x_{72} = 88.2263936883134$$
$$x_{73} = 28.012534494509$$
$$x_{74} = -50.0036830696375$$
$$x_{75} = 0.261799387799149$$
$$x_{76} = 37.9609112308767$$
$$x_{77} = 138.49187614575$$
$$x_{78} = 3.40339204138894$$
$$x_{79} = -91.3679863419031$$