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$$3 x \left(- \sin{\left(x \right)} + \cos{\left(x \right)}\right) + 3 \sin{\left(x \right)} + 3 \cos{\left(x \right)} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = 16.5536975718234$$
$$x_{2} = 85.6200787826806$$
$$x_{3} = -58.9218322634797$$
$$x_{4} = 1.40422360239197$$
$$x_{5} = -30.6631292754598$$
$$x_{6} = 35.3711814271828$$
$$x_{7} = -52.6406713811732$$
$$x_{8} = 47.9301486357051$$
$$x_{9} = 73.0557165239248$$
$$x_{10} = 76.1967450163399$$
$$x_{11} = -74.6262248358581$$
$$x_{12} = 63.6329650666866$$
$$x_{13} = -27.525250026105$$
$$x_{14} = 88.7612581637789$$
$$x_{15} = -96.6143241603692$$
$$x_{16} = -71.485220862291$$
$$x_{17} = 51.0704589102849$$
$$x_{18} = -14.9891811736395$$
$$x_{19} = 98.1849549323352$$
$$x_{20} = -5.67228968340682$$
$$x_{21} = 22.8203392800723$$
$$x_{22} = 4.1627493368126$$
$$x_{23} = 54.2109176513576$$
$$x_{24} = 32.2323394923898$$
$$x_{25} = 60.492188136142$$
$$x_{26} = -87.1906647520128$$
$$x_{27} = -40.0802511015808$$
$$x_{28} = -21.2527684271428$$
$$x_{29} = 41.6501075899818$$
$$x_{30} = -8.75313144558265$$
$$x_{31} = 79.3378181652015$$
$$x_{32} = -68.3442709758693$$
$$x_{33} = -80.9083698613449$$
$$x_{34} = -36.940777426275$$
$$x_{35} = 13.4261132241755$$
$$x_{36} = -43.2200322784808$$
$$x_{37} = -24.3883233381018$$
$$x_{38} = 82.4789308711661$$
$$x_{39} = 25.9566461271548$$
$$x_{40} = 44.7900180082647$$
$$x_{41} = 19.6857087307627$$
$$x_{42} = -11.8650548496173$$
$$x_{43} = 95.0436988589063$$
$$x_{44} = 7.20646720968486$$
$$x_{45} = -65.2033829872561$$
$$x_{46} = 91.9024657889622$$
$$x_{47} = -49.5002834509857$$
$$x_{48} = -84.0495006728084$$
$$x_{49} = -90.3318586299385$$
$$x_{50} = 57.3515004967328$$
$$x_{51} = -99.7555909164973$$
$$x_{52} = -62.0625662865258$$
$$x_{53} = -33.8016967133026$$
$$x_{54} = -18.119291621421$$
$$x_{55} = 10.3068958192079$$
$$x_{56} = 66.7738186988218$$
$$x_{57} = -55.781194869671$$
$$x_{58} = -77.7672763467182$$
$$x_{59} = 29.0940897621002$$
$$x_{60} = 101.326231870557$$
$$x_{61} = 38.5104711360153$$
$$x_{62} = -46.3600585879736$$
$$x_{63} = 69.9147387028857$$
$$x_{64} = -0.402628174188112$$
$$x_{65} = -93.4730793036062$$
$$x_{66} = -2.70973013143952$$
Signos de extremos en los puntos:
(16.553697571823395, -70.1035926897306)
(85.6200787826806, -363.230456444119)
(-58.92183226347968, 249.948168415584)
(1.4042236023919696, 4.85283796609462)
(-30.66312927545978, -130.023513524698)
(35.371181427182776, -150.007276275512)
(-52.64067138117324, 223.295166977936)
(47.93014863570506, -203.306154604854)
(73.05571652392481, -309.920122410268)
(76.19674501633988, 323.247574189303)
(-74.62622483585812, -316.583835705634)
(63.63296506668664, 269.938475993109)
(-27.52525002610497, 116.702753732209)
(88.76125816377889, 376.558228431005)
(-96.61432416036915, 409.877907823205)
(-71.485220862291, 303.256435962818)
(51.070458910284906, 216.632081692015)
(-14.989181173639471, 63.4526571637)
(98.18495493233517, -416.541880989337)
(-5.672289683406819, -23.7000051457511)
(22.820339280072254, -96.7256761441122)
(4.162749336812597, -17.172499957657)
(54.21091765135759, -229.958324027762)
(32.23233949238981, 136.684469028892)
(60.492188136142026, -256.611558150825)
(-87.19066475201284, -369.894334541072)
(-40.08025110158081, 169.993201948217)
(-21.25276842714282, 90.0682116392527)
(41.650107589981786, -176.655531164169)
(-8.753131445582648, 36.8963885617201)
(79.33781816520154, -336.575120739862)
(-68.34427097586932, -289.929151012458)
(-80.90836986134488, -343.238926106065)
(-36.94077742627499, -156.669051967046)
(13.426113224175548, 56.8048290036502)
(-43.22003227848084, -183.318005263312)
(-24.388323338101774, -103.384021426717)
(82.47893087116606, 349.902751237113)
(25.956646127154848, 110.043088305049)
(44.790018008264745, 189.980609024213)
(19.685708730762727, 83.4118375112009)
(-11.865054849617264, -50.1613241073371)
(95.04369885890632, 403.213946264871)
(7.206467209684859, 30.2842715782654)
(-65.2033829872561, 276.601997437678)
(91.90246578896223, -389.886060351692)
(-49.50028345098569, -209.969074994893)
(-84.04950067280843, 356.566595025288)
(-90.33185862993847, 383.222137290318)
(57.35150049673278, 243.284829853574)
(-99.75559091649727, -423.205865215076)
(-62.06256628652584, -263.274995176569)
(-33.801696713302576, 143.345737128658)
(-18.11929162142097, -76.7568353925031)
(10.306895819207908, -43.5240816776818)
(66.77381869882177, -283.265556644862)
(-55.78119486967102, -236.621546784402)
(-77.76727634671825, 329.911336335666)
(29.094089762100186, -123.362921104039)
(101.32623187055665, 429.869859986209)
(38.51047113601533, 163.331035314911)
(-46.360058587973604, 196.643329284637)
(69.91473870288569, 296.592778171943)
(-0.4026281741881116, -0.638000560322241)
(-93.47307930360616, -396.549996899364)
(-2.7097301314395232, 10.7854097749431)
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:
$$x_{1} = 16.5536975718234$$
$$x_{2} = 85.6200787826806$$
$$x_{3} = -30.6631292754598$$
$$x_{4} = 35.3711814271828$$
$$x_{5} = 47.9301486357051$$
$$x_{6} = 73.0557165239248$$
$$x_{7} = -74.6262248358581$$
$$x_{8} = 98.1849549323352$$
$$x_{9} = -5.67228968340682$$
$$x_{10} = 22.8203392800723$$
$$x_{11} = 4.1627493368126$$
$$x_{12} = 54.2109176513576$$
$$x_{13} = 60.492188136142$$
$$x_{14} = -87.1906647520128$$
$$x_{15} = 41.6501075899818$$
$$x_{16} = 79.3378181652015$$
$$x_{17} = -68.3442709758693$$
$$x_{18} = -80.9083698613449$$
$$x_{19} = -36.940777426275$$
$$x_{20} = -43.2200322784808$$
$$x_{21} = -24.3883233381018$$
$$x_{22} = -11.8650548496173$$
$$x_{23} = 91.9024657889622$$
$$x_{24} = -49.5002834509857$$
$$x_{25} = -99.7555909164973$$
$$x_{26} = -62.0625662865258$$
$$x_{27} = -18.119291621421$$
$$x_{28} = 10.3068958192079$$
$$x_{29} = 66.7738186988218$$
$$x_{30} = -55.781194869671$$
$$x_{31} = 29.0940897621002$$
$$x_{32} = -0.402628174188112$$
$$x_{33} = -93.4730793036062$$
Puntos máximos de la función:
$$x_{33} = -58.9218322634797$$
$$x_{33} = 1.40422360239197$$
$$x_{33} = -52.6406713811732$$
$$x_{33} = 76.1967450163399$$
$$x_{33} = 63.6329650666866$$
$$x_{33} = -27.525250026105$$
$$x_{33} = 88.7612581637789$$
$$x_{33} = -96.6143241603692$$
$$x_{33} = -71.485220862291$$
$$x_{33} = 51.0704589102849$$
$$x_{33} = -14.9891811736395$$
$$x_{33} = 32.2323394923898$$
$$x_{33} = -40.0802511015808$$
$$x_{33} = -21.2527684271428$$
$$x_{33} = -8.75313144558265$$
$$x_{33} = 13.4261132241755$$
$$x_{33} = 82.4789308711661$$
$$x_{33} = 25.9566461271548$$
$$x_{33} = 44.7900180082647$$
$$x_{33} = 19.6857087307627$$
$$x_{33} = 95.0436988589063$$
$$x_{33} = 7.20646720968486$$
$$x_{33} = -65.2033829872561$$
$$x_{33} = -84.0495006728084$$
$$x_{33} = -90.3318586299385$$
$$x_{33} = 57.3515004967328$$
$$x_{33} = -33.8016967133026$$
$$x_{33} = -77.7672763467182$$
$$x_{33} = 101.326231870557$$
$$x_{33} = 38.5104711360153$$
$$x_{33} = -46.3600585879736$$
$$x_{33} = 69.9147387028857$$
$$x_{33} = -2.70973013143952$$
Decrece en los intervalos
$$\left[98.1849549323352, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -99.7555909164973\right]$$