El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$e^{- 2 x - 4} \left(2 x + 5\right) = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - \frac{5}{2}$$
Solución numérica$$x_{1} = 56.774384232589$$
$$x_{2} = 88.737103656236$$
$$x_{3} = 96.7317968114856$$
$$x_{4} = 82.7417897073741$$
$$x_{5} = 54.7782727781725$$
$$x_{6} = 28.8862855081404$$
$$x_{7} = 60.7674287897793$$
$$x_{8} = 15.1750449615767$$
$$x_{9} = 36.8346732823359$$
$$x_{10} = 66.7586564991713$$
$$x_{11} = 110.724420054024$$
$$x_{12} = 38.8255114699693$$
$$x_{13} = 108.725353409128$$
$$x_{14} = 40.8173514565116$$
$$x_{15} = 24.9273080601523$$
$$x_{16} = 64.7613883303338$$
$$x_{17} = 100.729471811848$$
$$x_{18} = 84.74015048167$$
$$x_{19} = 72.7514132003699$$
$$x_{20} = 19.0325342555926$$
$$x_{21} = -2.5$$
$$x_{22} = 68.7560931709787$$
$$x_{23} = 52.782480243647$$
$$x_{24} = 80.7435141805966$$
$$x_{25} = 22.9545852802374$$
$$x_{26} = 30.8704530645089$$
$$x_{27} = 44.8034418740508$$
$$x_{28} = 48.7920234833324$$
$$x_{29} = 17.0913749517176$$
$$x_{30} = 26.9049536112628$$
$$x_{31} = 106.726323017889$$
$$x_{32} = 32.8568506746635$$
$$x_{33} = 94.7330359960606$$
$$x_{34} = 42.8100367236276$$
$$x_{35} = 62.7643058783751$$
$$x_{36} = 70.7536831986667$$
$$x_{37} = 102.728379793006$$
$$x_{38} = 50.7870476704722$$
$$x_{39} = 46.7974652351977$$
$$x_{40} = 98.7306098276648$$
$$x_{41} = 20.9886601399446$$
$$x_{42} = 92.7343309053532$$
$$x_{43} = 104.727331035849$$
$$x_{44} = 74.7492713092362$$
$$x_{45} = 58.7707795900672$$
$$x_{46} = 76.7472469646551$$
$$x_{47} = 86.7385903286241$$
$$x_{48} = 90.7356853881176$$
$$x_{49} = 78.7453307371258$$
$$x_{50} = 34.8450349019533$$