El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$2 \sin{\left(4 x - 8 \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = 2$$
$$x_{2} = \frac{\pi}{4} + 2$$
Solución numérica$$x_{1} = 9.85398163397448$$
$$x_{2} = 75.8274273593601$$
$$x_{3} = 78.1836218495525$$
$$x_{4} = 52.2654824574367$$
$$x_{5} = -107.170344712245$$
$$x_{6} = 12.9955742875643$$
$$x_{7} = 100.174770424681$$
$$x_{8} = -27.845130209103$$
$$x_{9} = -1.92699081698724$$
$$x_{10} = -53.7632696012188$$
$$x_{11} = -74.1836218495525$$
$$x_{12} = -100.101761241668$$
$$x_{13} = -12.1371669411541$$
$$x_{14} = -16.0641577581413$$
$$x_{15} = -67.1150383789755$$
$$x_{16} = -97.7455667514759$$
$$x_{17} = -35.6991118430775$$
$$x_{18} = 70.329640215578$$
$$x_{19} = 44.4115008234622$$
$$x_{20} = 31.845130209103$$
$$x_{21} = -57.6902604182061$$
$$x_{22} = 56.1924732744239$$
$$x_{23} = -79.6814089933346$$
$$x_{24} = -39.6261026600648$$
$$x_{25} = -52.1924732744239$$
$$x_{26} = 93.8915851175014$$
$$x_{27} = -62.4026493985908$$
$$x_{28} = 56.9778714378214$$
$$x_{29} = 71.9004365423729$$
$$x_{30} = 5.92699081698724$$
$$x_{31} = 66.4026493985908$$
$$x_{32} = -21.5619449019235$$
$$x_{33} = -49.8362787842316$$
$$x_{34} = -71.8274273593601$$
$$x_{35} = 34.2013246992954$$
$$x_{36} = -63.9734457253857$$
$$x_{37} = -89.8915851175014$$
$$x_{38} = 96.2477796076938$$
$$x_{39} = -61.6172512351933$$
$$x_{40} = 23.9911485751286$$
$$x_{41} = 97.8185759344887$$
$$x_{42} = -85.9645943005142$$
$$x_{43} = -83.6083998103219$$
$$x_{44} = 30.2743338823081$$
$$x_{45} = -93.8185759344887$$
$$x_{46} = -96.174770424681$$
$$x_{47} = 48.3384916404494$$
$$x_{48} = 85.2522053201295$$
$$x_{49} = 19.2787595947439$$
$$x_{50} = -5.85398163397448$$
$$x_{51} = 53.8362787842316$$
$$x_{52} = 89.9645943005142$$
$$x_{53} = -41.9822971502571$$
$$x_{54} = -60.0464549083984$$
$$x_{55} = 45.9822971502571$$
$$x_{56} = 0.429203673205103$$
$$x_{57} = 49.9092879672443$$
$$x_{58} = -31.7721210260903$$
$$x_{59} = 88.3937979737193$$
$$x_{60} = 2$$
$$x_{61} = -13.707963267949$$
$$x_{62} = -78.1106126665397$$
$$x_{63} = -17.6349540849362$$
$$x_{64} = 4.35619449019234$$
$$x_{65} = 12.2101761241668$$
$$x_{66} = 60.1194640914112$$
$$x_{67} = -45.9092879672443$$
$$x_{68} = 8.28318530717959$$
$$x_{69} = 67.9734457253857$$
$$x_{70} = 183.426975744811$$
$$x_{71} = 82.1106126665397$$
$$x_{72} = -30.2013246992954$$
$$x_{73} = -43.553093477052$$
$$x_{74} = 38.1283155162826$$
$$x_{75} = 16.1371669411541$$
$$x_{76} = 86.037603483527$$
$$x_{77} = 64.0464549083984$$
$$x_{78} = -86.7499924639117$$
$$x_{79} = 42.0553063332699$$
$$x_{80} = -19.9911485751286$$
$$x_{81} = -34.1283155162826$$
$$x_{82} = 27.9181393921158$$
$$x_{83} = -23.9181393921158$$
$$x_{84} = -75.7544181763474$$
$$x_{85} = -8.99557428756428$$
$$x_{86} = -56.1194640914112$$
$$x_{87} = 92.3207887907066$$
$$x_{88} = 74.2566310325652$$
$$x_{89} = -82.037603483527$$
$$x_{90} = -9.78097245096173$$
$$x_{91} = 22.4203522483337$$
$$x_{92} = -38.0553063332699$$
$$x_{93} = 20.0641577581413$$
$$x_{94} = 26.3473430653209$$
$$x_{95} = -67.9004365423729$$