El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\left(\left(1 - \cos{\left(3 x \right)}\right) - \sin{\left(3 x \right)}\right) e^{2 x} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = 0$$
$$x_{2} = - \frac{2 \pi}{3}$$
$$x_{3} = - \frac{\pi}{2}$$
$$x_{4} = \frac{\pi}{6}$$
$$x_{5} = \frac{2 \pi}{3}$$
$$x_{6} = \frac{5 \pi}{6}$$
Solución numérica$$x_{1} = -62.3082542961976$$
$$x_{2} = -31.75$$
$$x_{3} = -85.870199198121$$
$$x_{4} = -43.9822971502571$$
$$x_{5} = 46.0766922526503$$
$$x_{6} = -31.4159265358979$$
$$x_{7} = -53.9306738866248$$
$$x_{8} = -49.7418836818384$$
$$x_{9} = 15.1843644923507$$
$$x_{10} = -58.1194640914112$$
$$x_{11} = -97.9129710368819$$
$$x_{12} = -5.75958653158129$$
$$x_{13} = -95.8185759344887$$
$$x_{14} = -2.0943951023932$$
$$x_{15} = -100.007366139275$$
$$x_{16} = 6.28318530717959$$
$$x_{17} = -22.5147473507269$$
$$x_{18} = -66.497044500984$$
$$x_{19} = -92.1533845053006$$
$$x_{20} = -3.66519142918809$$
$$x_{21} = -75.398223686155$$
$$x_{22} = -51.8362787842316$$
$$x_{23} = -24.60914245312$$
$$x_{24} = -79.0634151153431$$
$$x_{25} = -39.7935069454707$$
$$x_{26} = -87.9645943005142$$
$$x_{27} = -16.2315620435473$$
$$x_{28} = -46.0766922526503$$
$$x_{29} = -90.0589894029074$$
$$x_{30} = -85.3466004225227$$
$$x_{31} = -26.7035375555132$$
$$x_{32} = -41.8879020478639$$
$$x_{33} = 12.5663706143592$$
$$x_{34} = -79.5870138909414$$
$$x_{35} = 8.37758040957278$$
$$x_{36} = -14.1371669411541$$
$$x_{37} = -7.85398163397448$$
$$x_{38} = -68.5914396033772$$
$$x_{39} = -35.081117965086$$
$$x_{40} = -70.6858347057703$$
$$x_{41} = -83.7758040957278$$
$$x_{42} = -35.6047167406843$$
$$x_{43} = -12.0427718387609$$
$$x_{44} = 92.1533845053006$$
$$x_{45} = 4.18879020478639$$
$$x_{46} = -37.6991118430775$$
$$x_{47} = -60.2138591938044$$
$$x_{48} = 10.9955742875643$$
$$x_{49} = -81.6814089933346$$
$$x_{50} = -93.7241808320955$$
$$x_{51} = -18.3259571459405$$
$$x_{52} = -28.7979326579064$$
$$x_{53} = -56.025068989018$$
$$x_{54} = -20.4203522483337$$
$$x_{55} = -9.94837673636768$$
$$x_{56} = 0$$
$$x_{57} = -72.7802298081635$$
$$x_{58} = 2.0943951023932$$
$$x_{59} = -64.4026493985908$$