El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\left(\left(x^{2} + 3 x\right) + 1\right) e^{x} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - \frac{3}{2} - \frac{\sqrt{5}}{2}$$
$$x_{2} = - \frac{3}{2} + \frac{\sqrt{5}}{2}$$
Solución numérica$$x_{1} = -65.7130850313755$$
$$x_{2} = -50.11664795977$$
$$x_{3} = -119.275460486142$$
$$x_{4} = -37.0550336649648$$
$$x_{5} = -117.283371808836$$
$$x_{6} = -97.383775351514$$
$$x_{7} = -46.288161799171$$
$$x_{8} = -121.267848247153$$
$$x_{9} = -71.6223362429761$$
$$x_{10} = -89.4392013163385$$
$$x_{11} = -52.0458577305852$$
$$x_{12} = -61.7869879057583$$
$$x_{13} = -79.5281091106993$$
$$x_{14} = -44.3935794587133$$
$$x_{15} = -115.291600231797$$
$$x_{16} = -95.3965875387763$$
$$x_{17} = -55.9262893552357$$
$$x_{18} = -57.8753118830868$$
$$x_{19} = -99.3715758502$$
$$x_{20} = -87.4549935549892$$
$$x_{21} = -75.5720474396862$$
$$x_{22} = -113.300165251554$$
$$x_{23} = -48.1967424276692$$
$$x_{24} = -73.5963144324851$$
$$x_{25} = -53.9828128207369$$
$$x_{26} = -35.3313051910704$$
$$x_{27} = -91.424245071494$$
$$x_{28} = -0.381966011250105$$
$$x_{29} = -2.61803398874989$$
$$x_{30} = -107.328100465941$$
$$x_{31} = -40.6623452864534$$
$$x_{32} = -77.5493625482196$$
$$x_{33} = -67.680471921532$$
$$x_{34} = -38.8380946782259$$
$$x_{35} = -63.7484663177983$$
$$x_{36} = -42.5166198499147$$
$$x_{37} = -59.8290926240591$$
$$x_{38} = -105.338242324585$$
$$x_{39} = -69.650311885485$$
$$x_{40} = -93.4100599216869$$
$$x_{41} = -81.5081551146594$$
$$x_{42} = -111.309088000122$$
$$x_{43} = -83.489384373542$$
$$x_{44} = -85.4716942132891$$
$$x_{45} = -109.318391420599$$
$$x_{46} = -103.348846677243$$
$$x_{47} = -101.359945990048$$