El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\cos{\left(2 x - 1 \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = \frac{1}{2} + \frac{\pi}{4}$$
$$x_{2} = \frac{1}{2} + \frac{3 \pi}{4}$$
Solución numérica$$x_{1} = 87.6791961371168$$
$$x_{2} = -0.285398163397448$$
$$x_{3} = 148.940252882118$$
$$x_{4} = -45.8384916404494$$
$$x_{5} = 73.5420291959627$$
$$x_{6} = -99.2455667514759$$
$$x_{7} = 26.4181393921158$$
$$x_{8} = -80.3960108299372$$
$$x_{9} = 4.42699081698724$$
$$x_{10} = 64.1172512351933$$
$$x_{11} = -23.8473430653209$$
$$x_{12} = 92.3915851175014$$
$$x_{13} = 13.8517687777566$$
$$x_{14} = 98.674770424681$$
$$x_{15} = -66.2588438887831$$
$$x_{16} = -33.2721210260903$$
$$x_{17} = -81.9668071567321$$
$$x_{18} = 7.56858347057703$$
$$x_{19} = 62.5464549083984$$
$$x_{20} = 93.9623814442964$$
$$x_{21} = -22.276546738526$$
$$x_{22} = 79.8252145031423$$
$$x_{23} = -61.5464549083984$$
$$x_{24} = 35.8429173528852$$
$$x_{25} = 71.9712328691678$$
$$x_{26} = 20.1349540849362$$
$$x_{27} = 76.6836218495525$$
$$x_{28} = 18.5641577581413$$
$$x_{29} = -74.1128255227576$$
$$x_{30} = -55.2632696012188$$
$$x_{31} = -30.1305283725005$$
$$x_{32} = -67.829640215578$$
$$x_{33} = -39.5553063332699$$
$$x_{34} = 106.528752058656$$
$$x_{35} = 43.6968989868597$$
$$x_{36} = 84.537603483527$$
$$x_{37} = 42.1261026600648$$
$$x_{38} = 95.5331777710912$$
$$x_{39} = -91.3915851175014$$
$$x_{40} = -58.4048622548086$$
$$x_{41} = 70.4004365423729$$
$$x_{42} = 78.2544181763474$$
$$x_{43} = -83.537603483527$$
$$x_{44} = 51.5508806208341$$
$$x_{45} = 29.5597320457056$$
$$x_{46} = -19.1349540849362$$
$$x_{47} = -44.2676953136546$$
$$x_{48} = -15.9933614313464$$
$$x_{49} = 27.9889357189107$$
$$x_{50} = -97.674770424681$$
$$x_{51} = 34.2721210260903$$
$$x_{52} = 12.2809724509617$$
$$x_{53} = -1.85619449019234$$
$$x_{54} = -75.6836218495525$$
$$x_{55} = 56.2632696012188$$
$$x_{56} = 86.1083998103219$$
$$x_{57} = -17.5641577581413$$
$$x_{58} = -52.121676947629$$
$$x_{59} = -88.2499924639117$$
$$x_{60} = 100.245566751476$$
$$x_{61} = 32.7013246992954$$
$$x_{62} = -59.9756585816035$$
$$x_{63} = -47.4092879672443$$
$$x_{64} = -31.7013246992954$$
$$x_{65} = 40.5553063332699$$
$$x_{66} = -37.984510006475$$
$$x_{67} = -3.42699081698724$$
$$x_{68} = -69.4004365423729$$
$$x_{69} = 49.9800842940392$$
$$x_{70} = 21.7057504117311$$
$$x_{71} = -11.2809724509617$$
$$x_{72} = 10.7101761241668$$
$$x_{73} = 5.99778714378214$$
$$x_{74} = -14.4225651045515$$
$$x_{75} = 65.6880475619882$$
$$x_{76} = 57.8340659280137$$
$$x_{77} = -9.71017612416683$$
$$x_{78} = -77.2544181763474$$
$$x_{79} = -89.8207887907066$$
$$x_{80} = -8.13937979737193$$
$$x_{81} = -96.1039740978861$$
$$x_{82} = 48.4092879672443$$
$$x_{83} = -25.4181393921158$$
$$x_{84} = -36.4137136796801$$
$$x_{85} = 54.6924732744239$$
$$x_{86} = -53.6924732744239$$