El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\left(- \sin{\left(2 x \right)} - \cos{\left(2 x \right)}\right) e^{3 x} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - \frac{5 \pi}{8}$$
$$x_{2} = - \frac{\pi}{8}$$
$$x_{3} = \frac{3 \pi}{8}$$
$$x_{4} = \frac{7 \pi}{8}$$
Solución numérica$$x_{1} = -14.5298660228528$$
$$x_{2} = -0.392699081698724$$
$$x_{3} = -36.5210145979813$$
$$x_{4} = -96.2112750161874$$
$$x_{5} = -45.9457925587507$$
$$x_{6} = -61.6537558266997$$
$$x_{7} = -56.941366846315$$
$$x_{8} = -68.0483752352495$$
$$x_{9} = -64.7953484802895$$
$$x_{10} = -58.5121631731099$$
$$x_{11} = -94.6404786893925$$
$$x_{12} = -31.8086256175967$$
$$x_{13} = -28.6670329640069$$
$$x_{14} = -9.8174770424681$$
$$x_{15} = -42.8041999051609$$
$$x_{16} = -52.2289778659303$$
$$x_{17} = -72.649330114264$$
$$x_{18} = -75.7909227678538$$
$$x_{19} = -38.0918109247762$$
$$x_{20} = -88.3572933822129$$
$$x_{21} = -100.923663996572$$
$$x_{22} = -53.7997741927252$$
$$x_{23} = -50.6581815391354$$
$$x_{24} = -6.67588438887831$$
$$x_{25} = -20.8130513300324$$
$$x_{26} = -23.9546439836222$$
$$x_{27} = 5.89048622548086$$
$$x_{28} = -74.2201264410589$$
$$x_{29} = -8.24668071567321$$
$$x_{30} = -66.3661448070844$$
$$x_{31} = -93.0696823625976$$
$$x_{32} = -34.9502182711865$$
$$x_{33} = -83.6449044018282$$
$$x_{34} = -86.786497055418$$
$$x_{35} = 1.17809724509617$$
$$x_{36} = -60.0829594999048$$
$$x_{37} = 7.46128255227576$$
$$x_{38} = -1.96349540849362$$
$$x_{39} = -97.7820713429823$$
$$x_{40} = -16.1006623496477$$
$$x_{41} = -78.9325154214436$$
$$x_{42} = -67.9369411338793$$
$$x_{43} = 4.31968989868597$$
$$x_{44} = -82.0741080750334$$
$$x_{45} = -39.6626072515711$$
$$x_{46} = 9.03207887907065$$
$$x_{47} = -44.3749962319558$$
$$x_{48} = -30.2378292908018$$
$$x_{49} = -17.6714586764426$$
$$x_{50} = -12.9590696960579$$
$$x_{51} = -22.3838476568273$$
$$x_{52} = -89.9280897090078$$
$$x_{53} = -80.5033117482384$$