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$$- \frac{\sin{\left(x \right)}}{x} - \frac{\cos{\left(x \right)}}{x^{2}} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = 47.1026627703624$$
$$x_{2} = 84.811211299318$$
$$x_{3} = -50.2455828375744$$
$$x_{4} = -100.521017074687$$
$$x_{5} = -65.9582857893902$$
$$x_{6} = 65.9582857893902$$
$$x_{7} = -78.5270825679419$$
$$x_{8} = -21.945612879981$$
$$x_{9} = 28.2389365752603$$
$$x_{10} = 53.3883466217256$$
$$x_{11} = -87.9532251106725$$
$$x_{12} = -25.0929104121121$$
$$x_{13} = -34.5285657554621$$
$$x_{14} = -69.100567727981$$
$$x_{15} = 94.2371684817036$$
$$x_{16} = -135.08108127842$$
$$x_{17} = -62.8159348889734$$
$$x_{18} = 50.2455828375744$$
$$x_{19} = -91.0952098694071$$
$$x_{20} = 91.0952098694071$$
$$x_{21} = 56.5309801938186$$
$$x_{22} = -53.3883466217256$$
$$x_{23} = -169.640108529775$$
$$x_{24} = -109.946647805931$$
$$x_{25} = -6.12125046689807$$
$$x_{26} = 2.79838604578389$$
$$x_{27} = -47.1026627703624$$
$$x_{28} = 62.8159348889734$$
$$x_{29} = 9.31786646179107$$
$$x_{30} = -2.79838604578389$$
$$x_{31} = -81.6691650818489$$
$$x_{32} = 12.4864543952238$$
$$x_{33} = -31.3840740178899$$
$$x_{34} = -94.2371684817036$$
$$x_{35} = 197.91528455229$$
$$x_{36} = 59.6735041304405$$
$$x_{37} = 97.3791034786112$$
$$x_{38} = 75.3849592185347$$
$$x_{39} = -40.8162093266346$$
$$x_{40} = -15.644128370333$$
$$x_{41} = -37.672573565113$$
$$x_{42} = -12.4864543952238$$
$$x_{43} = 15.644128370333$$
$$x_{44} = 69.100567727981$$
$$x_{45} = -84.811211299318$$
$$x_{46} = 31.3840740178899$$
$$x_{47} = 37.672573565113$$
$$x_{48} = -97.3791034786112$$
$$x_{49} = 6.12125046689807$$
$$x_{50} = 72.2427897046973$$
$$x_{51} = -75.3849592185347$$
$$x_{52} = 34.5285657554621$$
$$x_{53} = 43.9595528888955$$
$$x_{54} = 78.5270825679419$$
$$x_{55} = 40.8162093266346$$
$$x_{56} = 100.521017074687$$
$$x_{57} = 21.945612879981$$
$$x_{58} = -9.31786646179107$$
$$x_{59} = 25.0929104121121$$
$$x_{60} = -72.2427897046973$$
$$x_{61} = -18.7964043662102$$
$$x_{62} = 87.9532251106725$$
$$x_{63} = -59.6735041304405$$
$$x_{64} = -28.2389365752603$$
$$x_{65} = 18.7964043662102$$
$$x_{66} = 81.6691650818489$$
$$x_{67} = -56.5309801938186$$
$$x_{68} = -43.9595528888955$$
Signos de extremos en los puntos:
(47.10266277036235, 0.978774560583586)
(84.81121129931802, 0.988209925558923)
(-50.24558283757444, 0.980101693469645)
(-100.52101707468658, 0.990052323884637)
(-65.95828578939016, 1.01515935531684)
(65.95828578939016, 0.984840644683159)
(-78.52708256794193, 1.01273342767775)
(-21.945612879981045, 1.04551996040513)
(28.238936575260272, 0.964610084445831)
(53.38834662172563, 0.981272605535913)
(-87.95322511067255, 0.988631055084119)
(-25.092910412112097, 0.960179714449949)
(-34.52856575546206, 1.02894938891145)
(-69.10056772798097, 0.985529854025324)
(94.23716848170359, 1.01061092686295)
(-135.0810812784199, 1.00740275832667)
(-62.81593488897342, 0.984082489416574)
(50.24558283757444, 1.01989830653036)
(-91.09520986940714, 1.01097686424834)
(91.09520986940714, 0.989023135751658)
(56.53098019381864, 1.01768664855217)
(-53.38834662172563, 1.01872739446409)
(-169.6401085297751, 0.994105270064991)
(-109.94664780593057, 1.00909494432157)
(-6.1212504668980685, 0.838771965674936)
(2.798386045783887, 0.663491583081605)
(-47.10266277036235, 1.02122543941641)
(62.81593488897342, 1.01591751058343)
(9.317866461791066, 0.893292052284763)
(-2.798386045783887, 1.3365084169184)
(-81.66916508184887, 0.987756394432953)
(12.486454395223781, 1.07983118078)
(-31.38407401788986, 0.968152867888731)
(-94.23716848170359, 0.98938907313705)
(197.91528455229027, 0.994947397631339)
(59.67350413044053, 0.983244496342811)
(97.3791034786112, 0.989731397796919)
(75.38495921853475, 1.01326407865182)
(-40.81620932663458, 1.0244927205347)
(-15.644128370333028, 1.06379155303959)
(-37.67257356511297, 0.973464836989695)
(-12.486454395223781, 0.920168819219997)
(15.644128370333028, 0.936208446960406)
(69.10056772798097, 1.01447014597468)
(-84.81121129931802, 1.01179007444108)
(31.38407401788986, 1.03184713211127)
(37.67257356511297, 1.0265351630103)
(-97.3791034786112, 1.01026860220308)
(6.1212504668980685, 1.16122803432506)
(72.24278970469729, 0.986159114086845)
(-75.38495921853475, 0.986735921348175)
(34.52856575546206, 0.97105061108855)
(43.959552888895495, 1.02274230047253)
(78.52708256794193, 0.987266572322253)
(40.81620932663458, 0.975507279465304)
(100.52101707468658, 1.00994767611536)
(21.945612879981045, 0.954480039594871)
(-9.317866461791066, 1.10670794771524)
(25.092910412112097, 1.03982028555005)
(-72.24278970469729, 1.01384088591315)
(-18.796404366210158, 0.946873467438612)
(87.95322511067255, 1.01136894491588)
(-59.67350413044053, 1.01675550365719)
(-28.238936575260272, 1.03538991555417)
(18.796404366210158, 1.05312653256139)
(81.66916508184887, 1.01224360556705)
(-56.53098019381864, 0.98231335144783)
(-43.959552888895495, 0.977257699527469)
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:
$$x_{1} = 47.1026627703624$$
$$x_{2} = 84.811211299318$$
$$x_{3} = -50.2455828375744$$
$$x_{4} = -100.521017074687$$
$$x_{5} = 65.9582857893902$$
$$x_{6} = 28.2389365752603$$
$$x_{7} = 53.3883466217256$$
$$x_{8} = -87.9532251106725$$
$$x_{9} = -25.0929104121121$$
$$x_{10} = -69.100567727981$$
$$x_{11} = -62.8159348889734$$
$$x_{12} = 91.0952098694071$$
$$x_{13} = -169.640108529775$$
$$x_{14} = -6.12125046689807$$
$$x_{15} = 2.79838604578389$$
$$x_{16} = 9.31786646179107$$
$$x_{17} = -81.6691650818489$$
$$x_{18} = -31.3840740178899$$
$$x_{19} = -94.2371684817036$$
$$x_{20} = 197.91528455229$$
$$x_{21} = 59.6735041304405$$
$$x_{22} = 97.3791034786112$$
$$x_{23} = -37.672573565113$$
$$x_{24} = -12.4864543952238$$
$$x_{25} = 15.644128370333$$
$$x_{26} = 72.2427897046973$$
$$x_{27} = -75.3849592185347$$
$$x_{28} = 34.5285657554621$$
$$x_{29} = 78.5270825679419$$
$$x_{30} = 40.8162093266346$$
$$x_{31} = 21.945612879981$$
$$x_{32} = -18.7964043662102$$
$$x_{33} = -56.5309801938186$$
$$x_{34} = -43.9595528888955$$
Puntos máximos de la función:
$$x_{34} = -65.9582857893902$$
$$x_{34} = -78.5270825679419$$
$$x_{34} = -21.945612879981$$
$$x_{34} = -34.5285657554621$$
$$x_{34} = 94.2371684817036$$
$$x_{34} = -135.08108127842$$
$$x_{34} = 50.2455828375744$$
$$x_{34} = -91.0952098694071$$
$$x_{34} = 56.5309801938186$$
$$x_{34} = -53.3883466217256$$
$$x_{34} = -109.946647805931$$
$$x_{34} = -47.1026627703624$$
$$x_{34} = 62.8159348889734$$
$$x_{34} = -2.79838604578389$$
$$x_{34} = 12.4864543952238$$
$$x_{34} = 75.3849592185347$$
$$x_{34} = -40.8162093266346$$
$$x_{34} = -15.644128370333$$
$$x_{34} = 69.100567727981$$
$$x_{34} = -84.811211299318$$
$$x_{34} = 31.3840740178899$$
$$x_{34} = 37.672573565113$$
$$x_{34} = -97.3791034786112$$
$$x_{34} = 6.12125046689807$$
$$x_{34} = 43.9595528888955$$
$$x_{34} = 100.521017074687$$
$$x_{34} = -9.31786646179107$$
$$x_{34} = 25.0929104121121$$
$$x_{34} = -72.2427897046973$$
$$x_{34} = 87.9532251106725$$
$$x_{34} = -59.6735041304405$$
$$x_{34} = -28.2389365752603$$
$$x_{34} = 18.7964043662102$$
$$x_{34} = 81.6691650818489$$
Decrece en los intervalos
$$\left[197.91528455229, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -169.640108529775\right]$$