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$$\left(2 x - 1\right) \cos{\left(x \right)} + 3 \sin{\left(x \right)} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = -45.5856300973313$$
$$x_{2} = -83.27010955499$$
$$x_{3} = -2.09492138588594$$
$$x_{4} = -76.9883753378549$$
$$x_{5} = 45.5863507026718$$
$$x_{6} = 55.0053847101118$$
$$x_{7} = 105.257671677194$$
$$x_{8} = 58.1454793419602$$
$$x_{9} = -67.5662758307315$$
$$x_{10} = -11.1239094230235$$
$$x_{11} = 76.9886282578302$$
$$x_{12} = -58.1450361281976$$
$$x_{13} = -4.97958645877522$$
$$x_{14} = 5.03201855014322$$
$$x_{15} = 8.0501007584565$$
$$x_{16} = 80.1294476912726$$
$$x_{17} = -20.4916878532928$$
$$x_{18} = 39.3085402260932$$
$$x_{19} = -17.3625376671531$$
$$x_{20} = 42.4472447951378$$
$$x_{21} = -89.5520461210964$$
$$x_{22} = 2.27298232005305$$
$$x_{23} = 23.6267142359735$$
$$x_{24} = 36.1703424960528$$
$$x_{25} = 61.2857285828291$$
$$x_{26} = 17.3674549261486$$
$$x_{27} = 29.8961131447549$$
$$x_{28} = 33.032797548069$$
$$x_{29} = 92.6932520167225$$
$$x_{30} = -55.0048895078955$$
$$x_{31} = -8.02809006801769$$
$$x_{32} = -92.6930775072709$$
$$x_{33} = 48.7257798022585$$
$$x_{34} = -61.2853295847371$$
$$x_{35} = -95.834145479277$$
$$x_{36} = -23.6240435868063$$
$$x_{37} = -51.8649160864964$$
$$x_{38} = -39.3075716244322$$
$$x_{39} = 14.2458606217585$$
$$x_{40} = 11.1356848370861$$
$$x_{41} = 51.8654729829429$$
$$x_{42} = -70.7068969658595$$
$$x_{43} = -48.7251489329418$$
$$x_{44} = 86.4112560772636$$
$$x_{45} = 0.198412792932205$$
$$x_{46} = 73.8478749993387$$
$$x_{47} = 98.9753996408205$$
$$x_{48} = 20.495229888127$$
$$x_{49} = 95.8343087410424$$
$$x_{50} = -98.9752465735786$$
$$x_{51} = 89.5522330815776$$
$$x_{52} = -26.7585107959123$$
$$x_{53} = 70.7071967867599$$
$$x_{54} = -86.4110552844808$$
$$x_{55} = 64.4261096842988$$
$$x_{56} = -64.4257486040079$$
$$x_{57} = -73.8476001224597$$
$$x_{58} = 83.2703257734076$$
$$x_{59} = 26.7605953575094$$
$$x_{60} = -80.1292141995248$$
$$x_{61} = -36.1691989884899$$
$$x_{62} = -42.4464138779966$$
$$x_{63} = -33.0314272117789$$
$$x_{64} = -29.8944413312634$$
$$x_{65} = -14.2385913566217$$
$$x_{66} = 67.5666041499633$$
Signos de extremos en los puntos:
(-45.58563009733132, 92.1550076713403)
(-83.27010955499001, 167.531269623105)
(-2.0949213858859403, 4.99362510094841)
(-76.98837533785488, 154.967076336648)
(45.58635070267175, 90.1560896516624)
(55.00538471011178, -108.997022329722)
(105.25767167719371, -209.508185808685)
(58.145479341960204, 115.277959128447)
(-67.56627583073154, -136.121539675013)
(-11.123909423023479, -23.1846198986047)
(76.98862825783024, 152.967455848603)
(-58.14503612819762, 117.277293902343)
(-4.97958645877522, -10.8343120289872)
(5.032018550143224, -8.91917555623417)
(8.050100758456498, 15.0055980979256)
(80.12944769127256, -159.249480932697)
(-20.491687853292817, 41.9478742761831)
(39.30854022609317, 77.5977908493213)
(-17.362537667153074, -35.6834557894953)
(42.4472447951378, -83.8766385351894)
(-89.55204612109635, 180.095766612943)
(2.2729823200530452, 3.35299133763984)
(23.62671423597348, -46.2211683346969)
(36.17034249605284, -71.3197055241561)
(61.28572858282906, -121.559128129836)
(17.367454926148618, -33.6908819676733)
(29.89611314475495, -58.7667955576171)
(33.03279754806898, 65.0426025825689)
(92.69325201672254, -184.378371639055)
(-55.00488950789551, -110.996279020194)
(-8.028090068017692, 16.9715442883252)
(-92.69307750727087, -186.378109812048)
(48.72577980225852, -96.4360265469457)
(-61.2853295847371, -123.558529304126)
(-95.83414547927696, 192.660507916009)
(-23.624043586806327, -48.2171475834257)
(-51.86491608649638, 104.715524285881)
(-39.307571624432185, 79.5963360086251)
(14.245860621758535, 27.437962905159)
(11.135684837086066, -21.2025748245251)
(51.865472982942904, 102.716360270807)
(-70.70689696585954, 142.403267084147)
(-48.72514893294176, -98.4350794212227)
(86.41125607726357, -171.813785541528)
(0.19841279293220518, -1.09927450005257)
(73.84787499933874, -146.685530097094)
(98.97539964082053, -196.94318537473)
(20.495229888126993, 39.9532133611104)
(95.83430874104242, 190.660752863647)
(-98.97524657357857, -198.942955725531)
(89.55223308157761, 178.096047125781)
(-26.758510795912326, 54.489611113495)
(70.70719678675987, 140.403717000996)
(-86.41105528448084, -173.81348426917)
(64.42610968429884, 127.840495143801)
(-64.42574860400788, 129.839953254293)
(-73.84760012245974, -148.685117625865)
(83.27032577340765, 165.53159404719)
(26.7605953575094, 52.4927469501143)
(-80.12921419952481, -161.249130582586)
(-36.16919898848991, -73.3179875606176)
(-42.446413877996626, -85.8753907334664)
(-33.031427211778926, 67.0405431960901)
(-29.89444133126343, -60.7642820563578)
(-14.23859135662174, 29.4269486603258)
(67.56660414996325, -134.122032376309)
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:
$$x_{1} = 55.0053847101118$$
$$x_{2} = 105.257671677194$$
$$x_{3} = -67.5662758307315$$
$$x_{4} = -11.1239094230235$$
$$x_{5} = -4.97958645877522$$
$$x_{6} = 5.03201855014322$$
$$x_{7} = 80.1294476912726$$
$$x_{8} = -17.3625376671531$$
$$x_{9} = 42.4472447951378$$
$$x_{10} = 23.6267142359735$$
$$x_{11} = 36.1703424960528$$
$$x_{12} = 61.2857285828291$$
$$x_{13} = 17.3674549261486$$
$$x_{14} = 29.8961131447549$$
$$x_{15} = 92.6932520167225$$
$$x_{16} = -55.0048895078955$$
$$x_{17} = -92.6930775072709$$
$$x_{18} = 48.7257798022585$$
$$x_{19} = -61.2853295847371$$
$$x_{20} = -23.6240435868063$$
$$x_{21} = 11.1356848370861$$
$$x_{22} = -48.7251489329418$$
$$x_{23} = 86.4112560772636$$
$$x_{24} = 0.198412792932205$$
$$x_{25} = 73.8478749993387$$
$$x_{26} = 98.9753996408205$$
$$x_{27} = -98.9752465735786$$
$$x_{28} = -86.4110552844808$$
$$x_{29} = -73.8476001224597$$
$$x_{30} = -80.1292141995248$$
$$x_{31} = -36.1691989884899$$
$$x_{32} = -42.4464138779966$$
$$x_{33} = -29.8944413312634$$
$$x_{34} = 67.5666041499633$$
Puntos máximos de la función:
$$x_{34} = -45.5856300973313$$
$$x_{34} = -83.27010955499$$
$$x_{34} = -2.09492138588594$$
$$x_{34} = -76.9883753378549$$
$$x_{34} = 45.5863507026718$$
$$x_{34} = 58.1454793419602$$
$$x_{34} = 76.9886282578302$$
$$x_{34} = -58.1450361281976$$
$$x_{34} = 8.0501007584565$$
$$x_{34} = -20.4916878532928$$
$$x_{34} = 39.3085402260932$$
$$x_{34} = -89.5520461210964$$
$$x_{34} = 2.27298232005305$$
$$x_{34} = 33.032797548069$$
$$x_{34} = -8.02809006801769$$
$$x_{34} = -95.834145479277$$
$$x_{34} = -51.8649160864964$$
$$x_{34} = -39.3075716244322$$
$$x_{34} = 14.2458606217585$$
$$x_{34} = 51.8654729829429$$
$$x_{34} = -70.7068969658595$$
$$x_{34} = 20.495229888127$$
$$x_{34} = 95.8343087410424$$
$$x_{34} = 89.5522330815776$$
$$x_{34} = -26.7585107959123$$
$$x_{34} = 70.7071967867599$$
$$x_{34} = 64.4261096842988$$
$$x_{34} = -64.4257486040079$$
$$x_{34} = 83.2703257734076$$
$$x_{34} = 26.7605953575094$$
$$x_{34} = -33.0314272117789$$
$$x_{34} = -14.2385913566217$$
Decrece en los intervalos
$$\left[105.257671677194, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -98.9752465735786\right]$$