El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\sin{\left(3 x + 1 \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - \frac{1}{3}$$
$$x_{2} = - \frac{1}{3} + \frac{\pi}{3}$$
Solución numérica$$x_{1} = 62.4985197384625$$
$$x_{2} = 20.6106176905986$$
$$x_{3} = -62.1179888539326$$
$$x_{4} = 74.0176928016251$$
$$x_{5} = -29.6548647668381$$
$$x_{6} = 25.8466054465816$$
$$x_{7} = -49.5516182395734$$
$$x_{8} = -21.2772843572653$$
$$x_{9} = -13.9469014988891$$
$$x_{10} = -60.0235937515394$$
$$x_{11} = -69.4483717123088$$
$$x_{12} = 98.1032364791469$$
$$x_{13} = 1.76106176905986$$
$$x_{14} = 69.8289025968387$$
$$x_{15} = 96.0088413767537$$
$$x_{16} = -38.0324451764109$$
$$x_{17} = 38.4129760609408$$
$$x_{18} = -64.2123839563258$$
$$x_{19} = 47.8377540217102$$
$$x_{20} = -1.38053088452993$$
$$x_{21} = -86.2035325314543$$
$$x_{22} = -73.6371619170952$$
$$x_{23} = -20.2300868060687$$
$$x_{24} = 82.3952732111979$$
$$x_{25} = 100.19763158154$$
$$x_{26} = 18.5162225882054$$
$$x_{27} = 16.4218274858122$$
$$x_{28} = -23.3716794596585$$
$$x_{29} = 89.7256560695741$$
$$x_{30} = -66.306779058719$$
$$x_{31} = -93.5339153898305$$
$$x_{32} = 84.4896683135911$$
$$x_{33} = 34.2241858561544$$
$$x_{34} = 58.3097295336761$$
$$x_{35} = -99.8171006970101$$
$$x_{36} = -82.014742326668$$
$$x_{37} = 32.1297907537612$$
$$x_{38} = -57.9291986491462$$
$$x_{39} = -41.1740378300006$$
$$x_{40} = -71.542766814702$$
$$x_{41} = -3.47492598692313$$
$$x_{42} = -35.9380500740177$$
$$x_{43} = 28.9881981001714$$
$$x_{44} = -77.8259521218816$$
$$x_{45} = 5.94985197384625$$
$$x_{46} = 56.2153344312829$$
$$x_{47} = 3.85545687145306$$
$$x_{48} = 63.5457172896591$$
$$x_{49} = -18.1356917036755$$
$$x_{50} = -16.0412966012823$$
$$x_{51} = 30.035395651368$$
$$x_{52} = -40.126840278804$$
$$x_{53} = -88.2979276338476$$
$$x_{54} = 80.3008781088047$$
$$x_{55} = 76.1120879040183$$
$$x_{56} = 60.4041246360693$$
$$x_{57} = -95.6283104922237$$
$$x_{58} = -97.7227055946169$$
$$x_{59} = 67.7345074944455$$
$$x_{60} = 40.507371163334$$
$$x_{61} = 91.8200511719673$$
$$x_{62} = -5.56932108931632$$
$$x_{63} = 88.6784585183775$$
$$x_{64} = 93.9144462743605$$
$$x_{65} = 45.743358919317$$
$$x_{66} = -55.834803546753$$
$$x_{67} = 12.2330372810258$$
$$x_{68} = 10.1386421786326$$
$$x_{69} = 78.2064830064115$$
$$x_{70} = -25.4660745620517$$
$$x_{71} = -7.66371619170952$$
$$x_{72} = -47.4572231371802$$
$$x_{73} = -31.7492598692313$$
$$x_{74} = -75.7315570194884$$
$$x_{75} = 14.327432383419$$
$$x_{76} = 52.0265442264966$$
$$x_{77} = 54.1209393288897$$
$$x_{78} = -27.5604696644449$$
$$x_{79} = -79.9203472242748$$
$$x_{80} = 49.9321491241034$$
$$x_{81} = -724.994038761379$$
$$x_{82} = -9.75811129410271$$
$$x_{83} = 36.3185809585476$$
$$x_{84} = -33.8436549716245$$
$$x_{85} = 23.7522103441884$$
$$x_{86} = 27.9410005489748$$
$$x_{87} = -84.1091374290611$$
$$x_{88} = -42.2212353811972$$
$$x_{89} = -11.8525063964959$$
$$x_{90} = -51.6460133419666$$
$$x_{91} = 8.04424707623945$$
$$x_{92} = 71.9232976992319$$
$$x_{93} = -53.7404084443598$$