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−4(8x−81)cos(2x)+163sin(2x)=0Resolvermos esta ecuaciónRaíces de esta ecuación
x1=−72.0928234997439x2=40.5395084538546x3=21.4195644604296x4=97.2648772499214x5=−84.6831790656061x6=53.1780992694566x7=−53.1865162868496x8=−46.8745347430149x9=34.1999323668518x10=−0.485362558276441x11=14.8925876523829x12=−14.9900112041524x13=46.8637225983274x14=90.9730108075959x15=179.003392323252x16=65.7887551882277x17=−78.3889486119439x18=72.0882258411896x19=−21.469262706264x20=84.6798429343937x21=59.4857976886522x22=−65.7942704913902x23=27.834382800265x24=−8.2765436209072x25=8.00876143267673x26=−59.4925355374796x27=103.555681188122x28=−34.2200439239142x29=−90.9759025986992x30=78.3850572624003x31=−40.5539051427507x32=−97.2674079064454x33=1416.84981134451x34=−27.8644346285563Signos de extremos en los puntos:
(-72.09282349974393, 4.59389354372914)
(40.53950845385463, -2.51826357281154)
(21.419564460429562, 1.36541620628308)
(97.26487724992135, 6.03600591986278)
(-84.68317906560608, 5.37704419460649)
(53.17809926945661, -3.29690091496593)
(-53.18651628684961, -3.42111264145565)
(-46.87453474301491, 3.03111013420797)
(34.19993236685178, 2.13083942229892)
(-0.4853625582764406, -0.507657432693553)
(14.89258765238292, -0.995365828004467)
(-14.990011204152419, -1.11133040564379)
(46.863722598327406, 2.90712242054539)
(90.97301080759586, -5.64412041401817)
(179.00339232325229, -11.1357413416032)
(65.78875518822768, -4.07815101169087)
(-78.38894861194393, -4.98538014145867)
(72.08822584118958, 4.46932432786362)
(-21.46926270626403, 1.4857842065916)
(84.67984293439375, 5.25235682700065)
(59.48579768865222, 3.68730412130719)
(-65.79427049139015, -4.20263430613656)
(27.834382800265022, -1.74583718643573)
(-8.276543620907198, 0.758375279900881)
(8.008761432676732, 0.657927652486149)
(-59.49253553747962, 3.81167297570818)
(103.55568118812153, -6.42799097104595)
(-34.220043923914226, 2.25395858951351)
(-90.97590259869924, -5.76884940626111)
(78.38505726240027, -4.86074477885135)
(-40.55390514275072, -2.64191627024295)
(-97.2674079064454, 6.16076874563619)
(1416.8498113445055, 88.491937493712)
(-27.86443462855629, -1.86803002902737)
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=40.5395084538546x2=53.1780992694566x3=−53.1865162868496x4=−0.485362558276441x5=14.8925876523829x6=−14.9900112041524x7=90.9730108075959x8=179.003392323252x9=65.7887551882277x10=−78.3889486119439x11=−65.7942704913902x12=27.834382800265x13=103.555681188122x14=−90.9759025986992x15=78.3850572624003x16=−40.5539051427507x17=−27.8644346285563Puntos máximos de la función:
x17=−72.0928234997439x17=21.4195644604296x17=97.2648772499214x17=−84.6831790656061x17=−46.8745347430149x17=34.1999323668518x17=46.8637225983274x17=72.0882258411896x17=−21.469262706264x17=84.6798429343937x17=59.4857976886522x17=−8.2765436209072x17=8.00876143267673x17=−59.4925355374796x17=−34.2200439239142x17=−97.2674079064454x17=1416.84981134451Decrece en los intervalos
[179.003392323252,∞)Crece en los intervalos
(−∞,−90.9759025986992]