Para hallar los extremos hay que resolver la ecuación
dxdf(x)=0(la derivada es igual a cero),
y las raíces de esta ecuación serán los extremos de esta función:
dxdf(x)=primera derivada−xsin(x)−x2cos(x)=0Resolvermos esta ecuaciónRaíces de esta ecuación
x1=47.1026627703624x2=84.811211299318x3=−50.2455828375744x4=−100.521017074687x5=−65.9582857893902x6=65.9582857893902x7=−78.5270825679419x8=−21.945612879981x9=28.2389365752603x10=53.3883466217256x11=−87.9532251106725x12=−25.0929104121121x13=−34.5285657554621x14=−69.100567727981x15=94.2371684817036x16=−135.08108127842x17=−62.8159348889734x18=50.2455828375744x19=−91.0952098694071x20=91.0952098694071x21=56.5309801938186x22=−53.3883466217256x23=−169.640108529775x24=−109.946647805931x25=−6.12125046689807x26=2.79838604578389x27=−47.1026627703624x28=62.8159348889734x29=9.31786646179107x30=−2.79838604578389x31=−81.6691650818489x32=12.4864543952238x33=−31.3840740178899x34=−94.2371684817036x35=197.91528455229x36=59.6735041304405x37=97.3791034786112x38=75.3849592185347x39=−40.8162093266346x40=−15.644128370333x41=−37.672573565113x42=−12.4864543952238x43=15.644128370333x44=69.100567727981x45=−84.811211299318x46=31.3840740178899x47=37.672573565113x48=−97.3791034786112x49=6.12125046689807x50=72.2427897046973x51=−75.3849592185347x52=34.5285657554621x53=43.9595528888955x54=78.5270825679419x55=40.8162093266346x56=100.521017074687x57=21.945612879981x58=−9.31786646179107x59=25.0929104121121x60=−72.2427897046973x61=−18.7964043662102x62=87.9532251106725x63=−59.6735041304405x64=−28.2389365752603x65=18.7964043662102x66=81.6691650818489x67=−56.5309801938186x68=−43.9595528888955Signos 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:
x1=47.1026627703624x2=84.811211299318x3=−50.2455828375744x4=−100.521017074687x5=65.9582857893902x6=28.2389365752603x7=53.3883466217256x8=−87.9532251106725x9=−25.0929104121121x10=−69.100567727981x11=−62.8159348889734x12=91.0952098694071x13=−169.640108529775x14=−6.12125046689807x15=2.79838604578389x16=9.31786646179107x17=−81.6691650818489x18=−31.3840740178899x19=−94.2371684817036x20=197.91528455229x21=59.6735041304405x22=97.3791034786112x23=−37.672573565113x24=−12.4864543952238x25=15.644128370333x26=72.2427897046973x27=−75.3849592185347x28=34.5285657554621x29=78.5270825679419x30=40.8162093266346x31=21.945612879981x32=−18.7964043662102x33=−56.5309801938186x34=−43.9595528888955Puntos máximos de la función:
x34=−65.9582857893902x34=−78.5270825679419x34=−21.945612879981x34=−34.5285657554621x34=94.2371684817036x34=−135.08108127842x34=50.2455828375744x34=−91.0952098694071x34=56.5309801938186x34=−53.3883466217256x34=−109.946647805931x34=−47.1026627703624x34=62.8159348889734x34=−2.79838604578389x34=12.4864543952238x34=75.3849592185347x34=−40.8162093266346x34=−15.644128370333x34=69.100567727981x34=−84.811211299318x34=31.3840740178899x34=37.672573565113x34=−97.3791034786112x34=6.12125046689807x34=43.9595528888955x34=100.521017074687x34=−9.31786646179107x34=25.0929104121121x34=−72.2427897046973x34=87.9532251106725x34=−59.6735041304405x34=−28.2389365752603x34=18.7964043662102x34=81.6691650818489Decrece en los intervalos
[197.91528455229,∞)Crece en los intervalos
(−∞,−169.640108529775]