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$$\left(2 x - 1\right) \cos{\left(x \right)} + 2 \sin{\left(x \right)} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = 2.12300090681457$$
$$x_{2} = 39.2956785303244$$
$$x_{3} = -54.9958888407247$$
$$x_{4} = -61.2772425220152$$
$$x_{5} = -67.5589341430727$$
$$x_{6} = 80.1231711644351$$
$$x_{7} = 51.8557483406994$$
$$x_{8} = 4.93419822854993$$
$$x_{9} = 20.4703846071522$$
$$x_{10} = -89.5464955446878$$
$$x_{11} = -92.6877138973701$$
$$x_{12} = -36.1555897201517$$
$$x_{13} = -17.3347711916489$$
$$x_{14} = -11.0817037582484$$
$$x_{15} = 14.2099775813926$$
$$x_{16} = 0.247412484885142$$
$$x_{17} = -86.4053042434102$$
$$x_{18} = -1.95728275422062$$
$$x_{19} = -45.5747939110765$$
$$x_{20} = 36.1563536592178$$
$$x_{21} = 95.829065529839$$
$$x_{22} = -51.8553766970605$$
$$x_{23} = 17.3380791158534$$
$$x_{24} = 64.4182930958041$$
$$x_{25} = -14.2050661771509$$
$$x_{26} = -33.0165500205799$$
$$x_{27} = 83.2642872382528$$
$$x_{28} = -26.7402314854239$$
$$x_{29} = 98.9703235828905$$
$$x_{30} = 29.8791548121049$$
$$x_{31} = 240.336007491163$$
$$x_{32} = 89.5466202277414$$
$$x_{33} = 86.4054381545562$$
$$x_{34} = 48.715423408888$$
$$x_{35} = -48.7150023424838$$
$$x_{36} = 26.7416265193495$$
$$x_{37} = 76.9820942237331$$
$$x_{38} = -42.4347877496486$$
$$x_{39} = 61.2775087154266$$
$$x_{40} = -98.9702215094204$$
$$x_{41} = 102.1116023198$$
$$x_{42} = 54.9962192754584$$
$$x_{43} = 58.1368123734526$$
$$x_{44} = 42.4353425392198$$
$$x_{45} = 70.700078740623$$
$$x_{46} = -83.2641430354848$$
$$x_{47} = -20.4680078422429$$
$$x_{48} = -4.89564432915531$$
$$x_{49} = 92.6878302742345$$
$$x_{50} = 11.0897262388501$$
$$x_{51} = -70.699878750109$$
$$x_{52} = 7.98676475119172$$
$$x_{53} = 45.5752749499286$$
$$x_{54} = 33.0174658775265$$
$$x_{55} = -58.1365166573738$$
$$x_{56} = -64.4180522161792$$
$$x_{57} = -7.97148100902349$$
$$x_{58} = -39.2950316476879$$
$$x_{59} = -29.8780368458978$$
$$x_{60} = 67.5591531543674$$
$$x_{61} = 73.8410614412353$$
$$x_{62} = -80.123015436615$$
$$x_{63} = -76.9819255322054$$
$$x_{64} = -73.8408780976001$$
$$x_{65} = -23.6034090301611$$
$$x_{66} = -95.8289566560771$$
$$x_{67} = 23.6051982121417$$
Signos de extremos en los puntos:
(2.123000906814568, 2.76354903624568)
(39.2956785303244, 77.5655938310989)
(-54.995888840724724, -110.973762715585)
(-61.2772425220152, -123.538301033815)
(-67.5589341430727, -136.103177516664)
(80.12317116443509, -159.233784656253)
(51.85574834069936, 102.692030199991)
(4.934198228549927, -8.65112979640719)
(20.470384607152152, 39.8907890373943)
(-89.54649554468782, 180.081886742599)
(-92.68771389737012, -186.364697693097)
(-36.15558972015174, -73.283913689973)
(-17.334771191648883, -35.6136040006033)
(-11.081703758248404, -23.0775442284508)
(14.209977581392641, 27.3473053378206)
(0.2474124848851423, -0.123715373656181)
(-86.40530424341024, -173.799102851863)
(-1.9572827542206206, 4.55206306571846)
(-45.5747939110765, 92.1278916459743)
(36.156353659217835, -71.2846783594538)
(95.82906552983897, 190.647641945238)
(-51.85537669706051, 104.691658383599)
(17.338079115853432, -33.6169256769223)
(64.41829309580406, 127.820944089557)
(-14.20506617715089, 29.3423635380666)
(-33.016550020579906, 67.0032839397468)
(83.2642872382528, 165.516493293226)
(-26.740231485423934, 54.4437896263579)
(98.97032358289053, -196.930492607311)
(29.879154812104865, -58.7243014330717)
(240.33600749116286, 479.667845520984)
(89.54662022774141, 178.082011445089)
(86.40543815455618, -171.799236785429)
(48.71542340888797, -96.4101132552267)
(-48.715002342483764, -98.4096919670489)
(26.741626519349484, 52.4451870984841)
(76.98209422373313, 152.951115167863)
(-42.4347877496486, -85.8462938347437)
(61.27750871542658, -121.538567315839)
(-98.9702215094204, -198.930390520815)
(102.1116023198, 203.213363958583)
(54.99621927545844, -108.974093286877)
(58.13681237345261, 115.256278640346)
(42.43534253921977, -83.8468490094031)
(70.70007874062303, 140.385914650559)
(-83.26414303548475, 167.516349064459)
(-20.46800784224292, 41.8884051837394)
(-4.895644329155311, -10.6105958362832)
(92.68783027423446, -184.364814086894)
(11.089726238850124, -21.0856482225243)
(-70.69987875010902, 142.385714610033)
(7.986764751191716, 14.8417215197729)
(45.575274949928605, 90.1283729743018)
(33.01746587752653, 65.0042008467558)
(-58.13651665737381, 117.255982814905)
(-64.41805221617925, 129.820703137375)
(-7.971481009023492, 16.8261383769496)
(-39.29503164768789, 79.5649464248379)
(-29.878036845897785, -60.7231819016979)
(67.55915315436735, -134.103396587937)
(73.84106144123533, -146.668489856598)
(-80.12301543661505, -161.233628898112)
(-76.98192553220542, 154.950946440755)
(-73.8408780976001, -148.668306470931)
(-23.60340903016115, -48.165383634478)
(-95.8289566560771, 192.647533056656)
(23.605198212141747, -46.1671768296396)
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:
$$x_{1} = -54.9958888407247$$
$$x_{2} = -61.2772425220152$$
$$x_{3} = -67.5589341430727$$
$$x_{4} = 80.1231711644351$$
$$x_{5} = 4.93419822854993$$
$$x_{6} = -92.6877138973701$$
$$x_{7} = -36.1555897201517$$
$$x_{8} = -17.3347711916489$$
$$x_{9} = -11.0817037582484$$
$$x_{10} = 0.247412484885142$$
$$x_{11} = -86.4053042434102$$
$$x_{12} = 36.1563536592178$$
$$x_{13} = 17.3380791158534$$
$$x_{14} = 98.9703235828905$$
$$x_{15} = 29.8791548121049$$
$$x_{16} = 86.4054381545562$$
$$x_{17} = 48.715423408888$$
$$x_{18} = -48.7150023424838$$
$$x_{19} = -42.4347877496486$$
$$x_{20} = 61.2775087154266$$
$$x_{21} = -98.9702215094204$$
$$x_{22} = 54.9962192754584$$
$$x_{23} = 42.4353425392198$$
$$x_{24} = -4.89564432915531$$
$$x_{25} = 92.6878302742345$$
$$x_{26} = 11.0897262388501$$
$$x_{27} = -29.8780368458978$$
$$x_{28} = 67.5591531543674$$
$$x_{29} = 73.8410614412353$$
$$x_{30} = -80.123015436615$$
$$x_{31} = -73.8408780976001$$
$$x_{32} = -23.6034090301611$$
$$x_{33} = 23.6051982121417$$
Puntos máximos de la función:
$$x_{33} = 2.12300090681457$$
$$x_{33} = 39.2956785303244$$
$$x_{33} = 51.8557483406994$$
$$x_{33} = 20.4703846071522$$
$$x_{33} = -89.5464955446878$$
$$x_{33} = 14.2099775813926$$
$$x_{33} = -1.95728275422062$$
$$x_{33} = -45.5747939110765$$
$$x_{33} = 95.829065529839$$
$$x_{33} = -51.8553766970605$$
$$x_{33} = 64.4182930958041$$
$$x_{33} = -14.2050661771509$$
$$x_{33} = -33.0165500205799$$
$$x_{33} = 83.2642872382528$$
$$x_{33} = -26.7402314854239$$
$$x_{33} = 240.336007491163$$
$$x_{33} = 89.5466202277414$$
$$x_{33} = 26.7416265193495$$
$$x_{33} = 76.9820942237331$$
$$x_{33} = 102.1116023198$$
$$x_{33} = 58.1368123734526$$
$$x_{33} = 70.700078740623$$
$$x_{33} = -83.2641430354848$$
$$x_{33} = -20.4680078422429$$
$$x_{33} = -70.699878750109$$
$$x_{33} = 7.98676475119172$$
$$x_{33} = 45.5752749499286$$
$$x_{33} = 33.0174658775265$$
$$x_{33} = -58.1365166573738$$
$$x_{33} = -64.4180522161792$$
$$x_{33} = -7.97148100902349$$
$$x_{33} = -39.2950316476879$$
$$x_{33} = -76.9819255322054$$
$$x_{33} = -95.8289566560771$$
Decrece en los intervalos
$$\left[98.9703235828905, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -98.9702215094204\right]$$