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−xsin(x)+cos(x)=0Resolvermos esta ecuaciónRaíces de esta ecuación
x1=59.7070073053355x2=84.8347887180423x3=−78.5525459842429x4=6.43729817917195x5=−47.145097736761x6=−69.1295029738953x7=−9.52933440536196x8=40.8651703304881x9=22.0364967279386x10=18.90240995686x11=−40.8651703304881x12=0.86033358901938x13=28.309642854452x14=25.1724463266467x15=65.9885986984904x16=−147.661626855354x17=−100.540910786842x18=−0.86033358901938x19=44.0050179208308x20=12.6452872238566x21=3.42561845948173x22=97.3996388790738x23=−15.7712848748159x24=72.270467060309x25=−84.8347887180423x26=9.52933440536196x27=−44.0050179208308x28=−75.4114834888481x29=−65.9885986984904x30=−56.5663442798215x31=53.4257904773947x32=−53.4257904773947x33=87.9759605524932x34=69.1295029738953x35=47.145097736761x36=−6.43729817917195x37=−97.3996388790738x38=−18.90240995686x39=78.5525459842429x40=−25.1724463266467x41=15.7712848748159x42=−91.1171613944647x43=−28.309642854452x44=−81.6936492356017x45=−3.42561845948173x46=−12.6452872238566x47=−59.7070073053355x48=91.1171613944647x49=31.4477146375462x50=−72.270467060309x51=81.6936492356017x52=−116.247530303932x53=−94.2583883450399x54=−50.2853663377737x55=−31.4477146375462x56=−37.7256128277765x57=−87.9759605524932x58=34.5864242152889x59=94.2583883450399x60=62.8477631944545x61=−34.5864242152889x62=−62.8477631944545x63=37.7256128277765x64=−22.0364967279386x65=50.2853663377737x66=75.4114834888481x67=56.5663442798215x68=100.540910786842Signos de extremos en los puntos:
(59.70700730533546, -59.6986348402658)
(84.83478871804229, -84.8288955236568)
(-78.55254598424293, 78.5461815917343)
(6.437298179171947, 6.36100394483385)
(-47.14509773676103, 47.1344957575419)
(-69.12950297389526, -69.1222713069218)
(-9.529334405361963, 9.47729425947979)
(40.86517033048807, -40.8529404645174)
(22.036496727938566, -22.0138420791585)
(18.902409956860023, 18.876013697969)
(-40.86517033048807, 40.8529404645174)
(0.8603335890193797, 0.561096338191045)
(28.30964285445201, -28.2919975390943)
(25.172446326646664, 25.1526068178715)
(65.98859869849039, -65.9810229367917)
(-147.66162685535437, 147.658240851742)
(-100.54091078684232, -100.535938055826)
(-0.8603335890193797, -0.561096338191045)
(44.005017920830845, 43.9936599791065)
(12.645287223856643, 12.6059312978927)
(3.4256184594817283, -3.2883713955909)
(97.39963887907376, -97.3945057956234)
(-15.771284874815882, 15.7396769621337)
(72.27046706030896, -72.2635495982494)
(-84.83478871804229, 84.8288955236568)
(9.529334405361963, -9.47729425947979)
(-44.005017920830845, -43.9936599791065)
(-75.41148348884815, -75.4048540732019)
(-65.98859869849039, 65.9810229367917)
(-56.56634427982152, -56.5575071728762)
(53.42579047739466, -53.4164341598961)
(-53.42579047739466, 53.4164341598961)
(87.97596055249322, 87.9702777324248)
(69.12950297389526, 69.1222713069218)
(47.14509773676103, -47.1344957575419)
(-6.437298179171947, -6.36100394483385)
(-97.39963887907376, 97.3945057956234)
(-18.902409956860023, -18.876013697969)
(78.55254598424293, -78.5461815917343)
(-25.172446326646664, -25.1526068178715)
(15.771284874815882, -15.7396769621337)
(-91.11716139446474, 91.1116744496469)
(-28.30964285445201, 28.2919975390943)
(-81.69364923560168, -81.6875294965246)
(-3.4256184594817283, 3.2883713955909)
(-12.645287223856643, -12.6059312978927)
(-59.70700730533546, 59.6986348402658)
(91.11716139446474, -91.1116744496469)
(31.447714637546234, 31.4318272785346)
(-72.27046706030896, 72.2635495982494)
(81.69364923560168, 81.6875294965246)
(-116.2475303039321, 116.243229375987)
(-94.25838834503986, -94.2530842251087)
(-50.28536633777365, -50.2754260353972)
(-31.447714637546234, -31.4318272785346)
(-37.7256128277765, -37.71236621281)
(-87.97596055249322, -87.9702777324248)
(34.58642421528892, -34.5719767335884)
(94.25838834503986, 94.2530842251087)
(62.84776319445445, 62.8398089721545)
(-34.58642421528892, 34.5719767335884)
(-62.84776319445445, -62.8398089721545)
(37.7256128277765, 37.71236621281)
(-22.036496727938566, 22.0138420791585)
(50.28536633777365, 50.2754260353972)
(75.41148348884815, 75.4048540732019)
(56.56634427982152, 56.5575071728762)
(100.54091078684232, 100.535938055826)
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=59.7070073053355x2=84.8347887180423x3=−69.1295029738953x4=40.8651703304881x5=22.0364967279386x6=28.309642854452x7=65.9885986984904x8=−100.540910786842x9=−0.86033358901938x10=3.42561845948173x11=97.3996388790738x12=72.270467060309x13=9.52933440536196x14=−44.0050179208308x15=−75.4114834888481x16=−56.5663442798215x17=53.4257904773947x18=47.145097736761x19=−6.43729817917195x20=−18.90240995686x21=78.5525459842429x22=−25.1724463266467x23=15.7712848748159x24=−81.6936492356017x25=−12.6452872238566x26=91.1171613944647x27=−94.2583883450399x28=−50.2853663377737x29=−31.4477146375462x30=−37.7256128277765x31=−87.9759605524932x32=34.5864242152889x33=−62.8477631944545Puntos máximos de la función:
x33=−78.5525459842429x33=6.43729817917195x33=−47.145097736761x33=−9.52933440536196x33=18.90240995686x33=−40.8651703304881x33=0.86033358901938x33=25.1724463266467x33=−147.661626855354x33=44.0050179208308x33=12.6452872238566x33=−15.7712848748159x33=−84.8347887180423x33=−65.9885986984904x33=−53.4257904773947x33=87.9759605524932x33=69.1295029738953x33=−97.3996388790738x33=−91.1171613944647x33=−28.309642854452x33=−3.42561845948173x33=−59.7070073053355x33=31.4477146375462x33=−72.270467060309x33=81.6936492356017x33=−116.247530303932x33=94.2583883450399x33=62.8477631944545x33=−34.5864242152889x33=37.7256128277765x33=−22.0364967279386x33=50.2853663377737x33=75.4114834888481x33=56.5663442798215x33=100.540910786842Decrece en los intervalos
[97.3996388790738,∞)Crece en los intervalos
(−∞,−100.540910786842]