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$$- 2 x \sin{\left(x \right)} \sin{\left(x x \right)} + \cos{\left(x \right)} \cos{\left(x x \right)} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = 9.19740349378356$$
$$x_{2} = -13.4996223057844$$
$$x_{3} = -81.6093849425856$$
$$x_{4} = 37.7299282218133$$
$$x_{5} = 24.686568377777$$
$$x_{6} = -11.8877901034051$$
$$x_{7} = -19.817075034052$$
$$x_{8} = -74.1894047495946$$
$$x_{9} = -33.5830561024874$$
$$x_{10} = 66.2956311659985$$
$$x_{11} = 100.171022122574$$
$$x_{12} = 91.0861095210663$$
$$x_{13} = 8.12136575293037$$
$$x_{14} = 16.2463923074182$$
$$x_{15} = 72.2519772666015$$
$$x_{16} = 59.950090564826$$
$$x_{17} = 65.9592048186979$$
$$x_{18} = 82.1280228639246$$
$$x_{19} = 94.2483357150569$$
$$x_{20} = -75.4106863411887$$
$$x_{21} = -35.4935068559648$$
$$x_{22} = -5.8625197666758$$
$$x_{23} = 74.1682300291546$$
$$x_{24} = 34.5663110115024$$
$$x_{25} = 41.8690326983069$$
$$x_{26} = 63.8083801252282$$
$$x_{27} = -65.9592048186979$$
$$x_{28} = 19.9748396685938$$
$$x_{29} = 44.0295185243558$$
$$x_{30} = -18.8673893931125$$
$$x_{31} = -34.3680537314118$$
$$x_{32} = -55.9656531227802$$
$$x_{33} = 28.239867927311$$
$$x_{34} = -31.4248369496616$$
$$x_{35} = 46.2198495359116$$
$$x_{36} = -72.2639774276821$$
$$x_{37} = 9.87390760015023$$
$$x_{38} = -67.6557437976327$$
$$x_{39} = -7.7264840588988$$
$$x_{40} = 64.2499334209378$$
$$x_{41} = -1.75726069388394$$
$$x_{42} = 31.4630961908459$$
$$x_{43} = 40.885151628453$$
$$x_{44} = -44.0295185243558$$
$$x_{45} = -37.5563938018557$$
$$x_{46} = 34.0473413367003$$
$$x_{47} = -53.8781016081848$$
$$x_{48} = 21.9743280899463$$
$$x_{49} = 6.2748658163841$$
$$x_{50} = 56.4401788839842$$
$$x_{51} = -0.769078198679474$$
$$x_{52} = -100.734146933743$$
$$x_{53} = -81.7074951049546$$
$$x_{54} = -27.2863588637421$$
$$x_{55} = -15.7690801033127$$
$$x_{56} = -18.4182811611296$$
$$x_{57} = 25.746914047639$$
$$x_{58} = 100.59397869475$$
$$x_{59} = -83.9252404219482$$
$$x_{60} = 53.3771596043796$$
$$x_{61} = 12.5088958333929$$
$$x_{62} = -60.1331079745703$$
$$x_{63} = -8.85728446048035$$
$$x_{64} = -22.0135667558212$$
$$x_{65} = -47.1361693095921$$
$$x_{66} = 50.2515654936081$$
$$x_{67} = 52.249782936377$$
$$x_{68} = -72.1495298528441$$
$$x_{69} = -59.8192143176589$$
$$x_{70} = 86.178456137006$$
$$x_{71} = 75.3644838876308$$
$$x_{72} = -25.1474465956191$$
$$x_{73} = -103.666405298177$$
$$x_{74} = -89.7498877445714$$
$$x_{75} = -37.6759759619773$$
$$x_{76} = 3.9775707938788$$
$$x_{77} = -69.8716148687903$$
$$x_{78} = 62.7401715822144$$
$$x_{79} = 97.4213052309936$$
$$x_{80} = -60.0547265913059$$
$$x_{81} = 78.5398622551865$$
$$x_{82} = 18.2474374040137$$
$$x_{83} = 0.769078198679474$$
$$x_{84} = -34.6015033440174$$
$$x_{85} = 97.3930846549075$$
$$x_{86} = -47.2625437499565$$
$$x_{87} = 87.9596056058334$$
$$x_{88} = -91.0861095210663$$
$$x_{89} = 78.2492346142543$$
$$x_{90} = 37.7014286808617$$
$$x_{91} = -95.8437102158913$$
$$x_{92} = 48.2811173647424$$
$$x_{93} = 72.605863269931$$
$$x_{94} = -59.3968071491356$$
$$x_{95} = -94.0735686294802$$
$$x_{96} = -9.44394239617974$$
$$x_{97} = -3.9775707938788$$
Signos de extremos en los puntos:
(9.197403493783565, -0.219444549151449)
(-13.499622305784365, -0.803257422233564)
(-81.60938494258558, 0.0717037298822278)
(37.7299282218133, -0.0283066299172004)
(24.686568377777007, -0.431129913885276)
(-11.887790103405122, -0.626836406670419)
(-19.817075034052007, 0.82335634549733)
(-74.18940474959463, 0.935195365481653)
(-33.58305610248737, 0.827358223648153)
(66.29563116599846, 0.316559521590254)
(100.17102212257392, -0.352189715982702)
(91.08610952106635, -0.0193655152692017)
(8.12136575293037, -0.964328194224022)
(16.2463923074182, -0.512108585755021)
(72.25197726660154, 0.00259698996297122)
(59.95009056482602, -0.256790057404042)
(65.95920481869788, -0.0125706551854969)
(82.12802286392458, -0.431879117266966)
(94.24833571505688, -5.79759622024579e-5)
(-75.41068634118866, -0.0110023033178419)
(-35.493506855964775, -0.805141846498888)
(-5.8625197666757956, -0.40114348944827)
(74.16823002915456, 0.942483988302101)
(34.56631101150236, -0.0045664066564807)
(41.869032698306896, -0.856414929432106)
(63.8083801252282, 0.828546240587051)
(-65.95920481869788, 0.0125706551854969)
(19.974839668593823, -0.902325441859721)
(44.02951852435578, -0.0458972133262162)
(-18.86738939311252, 0.00995661505767042)
(-34.36805373141181, -0.187794288811805)
(-55.96565312278018, -0.550492566833726)
(28.239867927311, 0.0306538081431578)
(-31.42483694966162, -0.00435378652751852)
(46.21984953591158, 0.785803503162736)
(-72.2639774276821, 0.00534788961338665)
(9.873907600150234, 0.43180501092089)
(-67.65574379763274, -0.993789777923544)
(-7.7264840588988, 0.991849060306092)
(64.24993342093782, 0.988360851969678)
(-1.7572606938839426, 0.981253141179178)
(31.463096190845867, -0.0446877561610137)
(40.88515162845301, -0.0428424581895489)
(-44.02951852435578, 0.0458972133262162)
(-37.556393801855734, -0.141627478488972)
(34.04734133670026, -0.488164388671258)
(-53.87810160818477, 0.453725909035135)
(21.97432808994631, 0.00999902274859994)
(6.274865816384104, 0.000863929970449477)
(56.44017888398418, -0.1079197958395)
(-0.7690781986794745, -0.577323159838193)
(-100.73414693374315, -0.201728374377765)
(-81.7074951049546, 0.0253941030356869)
(-27.286358863742073, 0.834852272798559)
(-15.76908010331272, -0.0542309806174572)
(-18.418281161129585, 0.417303639559186)
(25.746914047638995, -0.576064287949661)
(100.59397869474962, -0.0627776054610027)
(-83.9252404219482, -0.781924483670467)
(53.377159604379635, -0.0285451673696211)
(12.508895833392868, -0.0471765001133663)
(-60.13310797457032, -0.428448223366849)
(-8.857284460480354, 0.53542465686823)
(-22.013566755821245, 0.0157480819332909)
(-47.136169309592134, -0.00929242848425308)
(50.25156549360814, -0.0113210208774044)
(52.24978293637695, -0.915710334196059)
(-72.14952985284408, 0.106675164042441)
(-59.819214317658925, -0.128330477287537)
(86.17845613700597, -0.976902620471384)
(75.36448388763084, -0.033100031153687)
(-25.147446595619083, 0.00874445792386331)
(-103.66640529817722, 0.00484174789378488)
(-89.74988774457135, -0.977082839821747)
(-37.675975961977294, 0.0200677494211038)
(3.977570793878804, 0.737211819463427)
(-69.87161486879026, -0.686416205685986)
(62.740171582214394, 0.0912110858862947)
(97.42130523099358, 0.0315232618744306)
(-60.05472659130586, 0.356365734179356)
(78.53986225518653, 3.31151227261698e-7)
(18.2474374040137, -0.56594004470794)
(0.7690781986794745, 0.577323159838193)
(-34.60150334401735, -0.0417759732698423)
(97.3930846549075, 0.002175353324985)
(-47.262543749956485, -0.137814653403373)
(87.95960560583337, 0.00329061342156182)
(-91.08610952106635, 0.0193655152692017)
(78.24923461425429, -0.286444228840489)
(37.701428680861696, 0.000398704807987242)
(-95.84371021589135, -0.999684141980109)
(48.28111736474238, -0.915682984372708)
(72.60586326993099, -0.342115323937686)
(-59.39680714913562, 0.289147412811862)
(-94.0735686294802, -0.173252126172693)
(-9.443942396179741, 0.00652318125840132)
(-3.977570793878804, -0.737211819463427)
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:
$$x_{1} = 9.19740349378356$$
$$x_{2} = -13.4996223057844$$
$$x_{3} = 37.7299282218133$$
$$x_{4} = 24.686568377777$$
$$x_{5} = -11.8877901034051$$
$$x_{6} = 100.171022122574$$
$$x_{7} = 91.0861095210663$$
$$x_{8} = 8.12136575293037$$
$$x_{9} = 16.2463923074182$$
$$x_{10} = 59.950090564826$$
$$x_{11} = 65.9592048186979$$
$$x_{12} = 82.1280228639246$$
$$x_{13} = 94.2483357150569$$
$$x_{14} = -75.4106863411887$$
$$x_{15} = -35.4935068559648$$
$$x_{16} = -5.8625197666758$$
$$x_{17} = 34.5663110115024$$
$$x_{18} = 41.8690326983069$$
$$x_{19} = 19.9748396685938$$
$$x_{20} = 44.0295185243558$$
$$x_{21} = -34.3680537314118$$
$$x_{22} = -55.9656531227802$$
$$x_{23} = -31.4248369496616$$
$$x_{24} = -67.6557437976327$$
$$x_{25} = 31.4630961908459$$
$$x_{26} = 40.885151628453$$
$$x_{27} = -37.5563938018557$$
$$x_{28} = 34.0473413367003$$
$$x_{29} = 56.4401788839842$$
$$x_{30} = -0.769078198679474$$
$$x_{31} = -100.734146933743$$
$$x_{32} = -15.7690801033127$$
$$x_{33} = 25.746914047639$$
$$x_{34} = 100.59397869475$$
$$x_{35} = -83.9252404219482$$
$$x_{36} = 53.3771596043796$$
$$x_{37} = 12.5088958333929$$
$$x_{38} = -60.1331079745703$$
$$x_{39} = -47.1361693095921$$
$$x_{40} = 50.2515654936081$$
$$x_{41} = 52.249782936377$$
$$x_{42} = -59.8192143176589$$
$$x_{43} = 86.178456137006$$
$$x_{44} = 75.3644838876308$$
$$x_{45} = -89.7498877445714$$
$$x_{46} = -69.8716148687903$$
$$x_{47} = 18.2474374040137$$
$$x_{48} = -34.6015033440174$$
$$x_{49} = -47.2625437499565$$
$$x_{50} = 78.2492346142543$$
$$x_{51} = -95.8437102158913$$
$$x_{52} = 48.2811173647424$$
$$x_{53} = 72.605863269931$$
$$x_{54} = -94.0735686294802$$
$$x_{55} = -3.9775707938788$$
Puntos máximos de la función:
$$x_{55} = -81.6093849425856$$
$$x_{55} = -19.817075034052$$
$$x_{55} = -74.1894047495946$$
$$x_{55} = -33.5830561024874$$
$$x_{55} = 66.2956311659985$$
$$x_{55} = 72.2519772666015$$
$$x_{55} = 74.1682300291546$$
$$x_{55} = 63.8083801252282$$
$$x_{55} = -65.9592048186979$$
$$x_{55} = -18.8673893931125$$
$$x_{55} = 28.239867927311$$
$$x_{55} = 46.2198495359116$$
$$x_{55} = -72.2639774276821$$
$$x_{55} = 9.87390760015023$$
$$x_{55} = -7.7264840588988$$
$$x_{55} = 64.2499334209378$$
$$x_{55} = -1.75726069388394$$
$$x_{55} = -44.0295185243558$$
$$x_{55} = -53.8781016081848$$
$$x_{55} = 21.9743280899463$$
$$x_{55} = 6.2748658163841$$
$$x_{55} = -81.7074951049546$$
$$x_{55} = -27.2863588637421$$
$$x_{55} = -18.4182811611296$$
$$x_{55} = -8.85728446048035$$
$$x_{55} = -22.0135667558212$$
$$x_{55} = -72.1495298528441$$
$$x_{55} = -25.1474465956191$$
$$x_{55} = -103.666405298177$$
$$x_{55} = -37.6759759619773$$
$$x_{55} = 3.9775707938788$$
$$x_{55} = 62.7401715822144$$
$$x_{55} = 97.4213052309936$$
$$x_{55} = -60.0547265913059$$
$$x_{55} = 78.5398622551865$$
$$x_{55} = 0.769078198679474$$
$$x_{55} = 97.3930846549075$$
$$x_{55} = 87.9596056058334$$
$$x_{55} = -91.0861095210663$$
$$x_{55} = 37.7014286808617$$
$$x_{55} = -59.3968071491356$$
$$x_{55} = -9.44394239617974$$
Decrece en los intervalos
$$\left[100.59397869475, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -100.734146933743\right]$$