El gráfico de la función cruce el eje T con f = 0
o sea hay que resolver la ecuación:
$$\frac{8 \sin{\left(2 t \right)}}{5} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje T:
Solución analítica$$t_{1} = 0$$
$$t_{2} = \frac{\pi}{2}$$
Solución numérica$$t_{1} = 89.5353906273091$$
$$t_{2} = -15.707963267949$$
$$t_{3} = -31.4159265358979$$
$$t_{4} = 42.4115008234622$$
$$t_{5} = 21.9911485751286$$
$$t_{6} = 0$$
$$t_{7} = -42.4115008234622$$
$$t_{8} = -29.845130209103$$
$$t_{9} = -21.9911485751286$$
$$t_{10} = -36.1283155162826$$
$$t_{11} = 28.2743338823081$$
$$t_{12} = 86.3937979737193$$
$$t_{13} = 72.2566310325652$$
$$t_{14} = -94.2477796076938$$
$$t_{15} = -61.261056745001$$
$$t_{16} = -40.8407044966673$$
$$t_{17} = 87.9645943005142$$
$$t_{18} = -95.8185759344887$$
$$t_{19} = -50.2654824574367$$
$$t_{20} = 23.5619449019235$$
$$t_{21} = -43.9822971502571$$
$$t_{22} = -97.3893722612836$$
$$t_{23} = 50.2654824574367$$
$$t_{24} = 590.619418874881$$
$$t_{25} = -14.1371669411541$$
$$t_{26} = 59.6902604182061$$
$$t_{27} = -119.380520836412$$
$$t_{28} = 58.1194640914112$$
$$t_{29} = -53.4070751110265$$
$$t_{30} = -48.6946861306418$$
$$t_{31} = -23.5619449019235$$
$$t_{32} = -86.3937979737193$$
$$t_{33} = -17.2787595947439$$
$$t_{34} = 12.5663706143592$$
$$t_{35} = -81.6814089933346$$
$$t_{36} = 94.2477796076938$$
$$t_{37} = 81.6814089933346$$
$$t_{38} = -67.5442420521806$$
$$t_{39} = -80.1106126665397$$
$$t_{40} = -1.5707963267949$$
$$t_{41} = 31.4159265358979$$
$$t_{42} = 92.6769832808989$$
$$t_{43} = 36.1283155162826$$
$$t_{44} = -39.2699081698724$$
$$t_{45} = -28.2743338823081$$
$$t_{46} = 4.71238898038469$$
$$t_{47} = 48.6946861306418$$
$$t_{48} = -72.2566310325652$$
$$t_{49} = 37.6991118430775$$
$$t_{50} = 70.6858347057703$$
$$t_{51} = -45.553093477052$$
$$t_{52} = -89.5353906273091$$
$$t_{53} = 65.9734457253857$$
$$t_{54} = 73.8274273593601$$
$$t_{55} = 20.4203522483337$$
$$t_{56} = -483.805268652828$$
$$t_{57} = -87.9645943005142$$
$$t_{58} = 1.5707963267949$$
$$t_{59} = 45.553093477052$$
$$t_{60} = 78.5398163397448$$
$$t_{61} = -6.28318530717959$$
$$t_{62} = 95.8185759344887$$
$$t_{63} = 15.707963267949$$
$$t_{64} = -20.4203522483337$$
$$t_{65} = -58.1194640914112$$
$$t_{66} = 56.5486677646163$$
$$t_{67} = 113.097335529233$$
$$t_{68} = 80.1106126665397$$
$$t_{69} = 7.85398163397448$$
$$t_{70} = 26.7035375555132$$
$$t_{71} = 29.845130209103$$
$$t_{72} = -65.9734457253857$$
$$t_{73} = 43.9822971502571$$
$$t_{74} = 14.1371669411541$$
$$t_{75} = -37.6991118430775$$
$$t_{76} = -59.6902604182061$$
$$t_{77} = -64.4026493985908$$
$$t_{78} = -83.2522053201295$$
$$t_{79} = -75.398223686155$$
$$t_{80} = 51.8362787842316$$
$$t_{81} = 100.530964914873$$
$$t_{82} = 64.4026493985908$$
$$t_{83} = 34.5575191894877$$
$$t_{84} = -73.8274273593601$$
$$t_{85} = 6.28318530717959$$
$$t_{86} = -9.42477796076938$$
$$t_{87} = -51.8362787842316$$
$$t_{88} = 67.5442420521806$$
$$t_{89} = -7.85398163397448$$