El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\left(- \sin{\left(3 x \right)} - \cos{\left(3 x \right)}\right) e^{2 x} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - \frac{3 \pi}{4}$$
$$x_{2} = - \frac{5 \pi}{12}$$
$$x_{3} = - \frac{\pi}{12}$$
$$x_{4} = \frac{\pi}{4}$$
$$x_{5} = \frac{7 \pi}{12}$$
$$x_{6} = \frac{11 \pi}{12}$$
Solución numérica$$x_{1} = -92.4151838930998$$
$$x_{2} = -55.7632696012188$$
$$x_{3} = -9.68657734856853$$
$$x_{4} = -90.3207887907066$$
$$x_{5} = -68.329640215578$$
$$x_{6} = -64.1408500107916$$
$$x_{7} = -103.934356956262$$
$$x_{8} = 1.83259571459405$$
$$x_{9} = -17.0169602069447$$
$$x_{10} = -18.0641577581413$$
$$x_{11} = -86.1319985859202$$
$$x_{12} = -11.7809724509617$$
$$x_{13} = -79.8488132787406$$
$$x_{14} = -51.5744793964324$$
$$x_{15} = -40.0553063332699$$
$$x_{16} = -29.5833308213039$$
$$x_{17} = -15.9697626557481$$
$$x_{18} = -48.4328867428426$$
$$x_{19} = 3.92699081698724$$
$$x_{20} = -73.565627971561$$
$$x_{21} = -2.35619449019234$$
$$x_{22} = -24.8430658466266$$
$$x_{23} = -30.6305283725005$$
$$x_{24} = -13.8753675533549$$
$$x_{25} = 13.3517687777566$$
$$x_{26} = -26.4417381677141$$
$$x_{27} = -99.7455667514759$$
$$x_{28} = -42.1497014356631$$
$$x_{29} = 10.2101761241668$$
$$x_{30} = -81.9432083811338$$
$$x_{31} = -66.2352451131848$$
$$x_{32} = -44.2440965380563$$
$$x_{33} = 14.3989663289532$$
$$x_{34} = 8.11578102177363$$
$$x_{35} = -35.8665161284835$$
$$x_{36} = -4.45058959258554$$
$$x_{37} = -37.9609112308767$$
$$x_{38} = -31.6777259236971$$
$$x_{39} = -77.7544181763474$$
$$x_{40} = -70.4240353179712$$
$$x_{41} = -57.857664703612$$
$$x_{42} = 12.30457122656$$
$$x_{43} = -75.6600230739542$$
$$x_{44} = -88.2263936883134$$
$$x_{45} = -62.0464549083984$$
$$x_{46} = -20.1585528605345$$
$$x_{47} = -22.2529479629277$$
$$x_{48} = -7.59218224617533$$
$$x_{49} = -95.5567765466895$$
$$x_{50} = -84.037603483527$$
$$x_{51} = -59.9520598060052$$
$$x_{52} = 6.02138591938044$$
$$x_{53} = -46.8370435162488$$
$$x_{54} = -33.7721210260903$$
$$x_{55} = -97.6511716490827$$
$$x_{56} = -53.6688744988256$$
$$x_{57} = -0.261799387799149$$