Para hallar los extremos hay que resolver la ecuación
$$\frac{d}{d x} f{\left(x \right)} = 0$$
(la derivada es igual a cero),
y las raíces de esta ecuación serán los extremos de esta función:
$$\frac{d}{d x} f{\left(x \right)} = $$
primera derivada$$\left(- x - 1\right) e^{x} - e^{x} - \frac{\sin{\left(x \right)}}{2} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = -59.6902604182061$$
$$x_{2} = -62.8318530717959$$
$$x_{3} = -97.3893722612836$$
$$x_{4} = -56.5486677646163$$
$$x_{5} = -37.6991118430775$$
$$x_{6} = -81.6814089933346$$
$$x_{7} = -84.8230016469244$$
$$x_{8} = -113.097335529233$$
$$x_{9} = -87.9645943005142$$
$$x_{10} = -100.530964914873$$
$$x_{11} = -18.8495557020762$$
$$x_{12} = -9.42597507233309$$
$$x_{13} = -0.949419181488109$$
$$x_{14} = -15.7079673995606$$
$$x_{15} = -94.2477796076938$$
$$x_{16} = -34.5575191894878$$
$$x_{17} = -69.1150383789755$$
$$x_{18} = -50.2654824574367$$
$$x_{19} = -78.5398163397448$$
$$x_{20} = -53.4070751110265$$
$$x_{21} = -12.5662969123378$$
$$x_{22} = -43.9822971502571$$
$$x_{23} = -232.477856365645$$
$$x_{24} = -65.9734457253857$$
$$x_{25} = -31.4159265358966$$
$$x_{26} = -3.23889333917348$$
$$x_{27} = -28.2743338823358$$
$$x_{28} = -47.1238898038469$$
$$x_{29} = -75.398223686155$$
$$x_{30} = -72.2566310325652$$
$$x_{31} = -91.106186954104$$
$$x_{32} = -21.9911485863806$$
$$x_{33} = -6.26698764944339$$
$$x_{34} = -40.8407044966673$$
$$x_{35} = -25.1327412281557$$
Signos de extremos en los puntos:
(-59.69026041820607, -0.5)
(-62.83185307179586, 0.5)
(-97.3893722612836, -0.5)
(-56.548667764616276, 0.5)
(-37.69911184307752, 0.500000000000002)
(-81.68140899333463, 0.5)
(-84.82300164692441, -0.5)
(-113.09733552923255, 0.5)
(-87.96459430051421, 0.5)
(-100.53096491487338, 0.5)
(-18.84955570207621, 0.500000116243677)
(-9.425975072333086, -0.499320483123082)
(-0.9494191814881093, 0.271504676449376)
(-15.707967399560632, -0.499997783488795)
(-94.2477796076938, 0.5)
(-34.55751918948779, -0.499999999999967)
(-69.11503837897546, 0.5)
(-50.26548245743669, 0.5)
(-78.53981633974483, -0.5)
(-53.40707511102649, -0.5)
(-12.566296912337776, 0.500040337252057)
(-43.982297150257104, 0.5)
(-232.4778563656447, 0.5)
(-65.97344572538566, -0.5)
(-31.415926535896595, 0.500000000000691)
(-3.238893339173482, -0.409854137097742)
(-28.274333882335757, -0.499999999985666)
(-47.1238898038469, -0.5)
(-75.39822368615503, 0.5)
(-72.25663103256524, -0.5)
(-91.106186954104, -0.5)
(-21.991148586380643, -0.499999994092527)
(-6.266987649443386, 0.50993082237036)
(-40.840704496667314, -0.5)
(-25.132741228155684, 0.500000000293492)
Intervalos de crecimiento y decrecimiento de la función:Hallemos los intervalos donde la función crece y decrece y también los puntos mínimos y máximos de la función, para lo cual miramos cómo se comporta la función en los extremos con desviación mínima del extremo:
Puntos mínimos de la función:
$$x_{1} = -59.6902604182061$$
$$x_{2} = -97.3893722612836$$
$$x_{3} = -84.8230016469244$$
$$x_{4} = -9.42597507233309$$
$$x_{5} = -15.7079673995606$$
$$x_{6} = -34.5575191894878$$
$$x_{7} = -78.5398163397448$$
$$x_{8} = -53.4070751110265$$
$$x_{9} = -65.9734457253857$$
$$x_{10} = -3.23889333917348$$
$$x_{11} = -28.2743338823358$$
$$x_{12} = -47.1238898038469$$
$$x_{13} = -72.2566310325652$$
$$x_{14} = -91.106186954104$$
$$x_{15} = -21.9911485863806$$
$$x_{16} = -40.8407044966673$$
Puntos máximos de la función:
$$x_{16} = -62.8318530717959$$
$$x_{16} = -56.5486677646163$$
$$x_{16} = -37.6991118430775$$
$$x_{16} = -81.6814089933346$$
$$x_{16} = -113.097335529233$$
$$x_{16} = -87.9645943005142$$
$$x_{16} = -100.530964914873$$
$$x_{16} = -18.8495557020762$$
$$x_{16} = -0.949419181488109$$
$$x_{16} = -94.2477796076938$$
$$x_{16} = -69.1150383789755$$
$$x_{16} = -50.2654824574367$$
$$x_{16} = -12.5662969123378$$
$$x_{16} = -43.9822971502571$$
$$x_{16} = -232.477856365645$$
$$x_{16} = -31.4159265358966$$
$$x_{16} = -75.398223686155$$
$$x_{16} = -6.26698764944339$$
$$x_{16} = -25.1327412281557$$
Decrece en los intervalos
$$\left[-3.23889333917348, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -97.3893722612836\right]$$