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 derivadax−cos(x)+x2sin(x)+x24cos(x)−x34sin(x)−x2(−sin(x)−x2cos(x))+x22sin(x)=0Resolvermos esta ecuaciónRaíces de esta ecuación
x1=−13.9205214266357x2=−3.87023858022217x3=−98.9298409677395x4=36.0450220033785x5=−89.5018675871561x6=−10.7130109882558x7=7.44308705395446x8=−83.2161494163012x9=98.9298409677395x10=26.5905550258527x11=−42.3406072405316x12=51.7783178293904x13=−23.4336891696933x14=−39.1933145376163x15=−17.1027407890472x16=67.499787704256x17=−80.0731410729394x18=89.5018675871561x19=−36.0450220033785x20=−92.644597693687x21=86.3590546280651x22=−26.5905550258527x23=−61.2120336791686x24=249.744603496217x25=−48.6329734602127x26=70.6433593524237x27=−64.356022448055x28=−212.043355752614x29=73.7867621864701x30=−95.7872531120814x31=45.4871087849823x32=10.7130109882558x33=58.0677849921727x34=23.4336891696933x35=−70.6433593524237x36=−73.7867621864701x37=83.2161494163012x38=3.87023858022217x39=39.1933145376163x40=20.2720010891386x41=17.1027407890472x42=−20.2720010891386x43=61.2120336791686x44=−7.44308705395446x45=92.644597693687x46=76.9300169373264x47=48.6329734602127x48=−51.7783178293904x49=−67.499787704256x50=−54.9232316104305x51=42.3406072405316x52=95.7872531120814x53=54.9232316104305x54=−86.3590546280651x55=−45.4871087849823x56=29.7441555138788x57=−29.7441555138788x58=1148.2495022125x59=64.356022448055x60=80.0731410729394x61=−58.0677849921727x62=13.9205214266357x63=32.8954402073454x64=−76.9300169373264x65=230.894066823744x66=−32.8954402073454Signos de extremos en los puntos:
(-13.920521426635718, -0.0716515891912541)
(-3.870238580222165, 0.248692236445789)
(-98.92984096773947, 0.0101076571692611)
(36.04502200337846, 0.027732411296845)
(-89.5018675871561, -0.0111722538908926)
(-10.713010988255775, 0.0929394035698334)
(7.443087053954458, -0.133143202113607)
(-83.21614941630125, -0.012016030684702)
(98.92984096773947, 0.0101076571692611)
(26.590555025852712, -0.0375807705734432)
(-42.34060724053156, 0.0236114046136127)
(51.77831782939038, -0.0193095024183706)
(-23.433689169693317, 0.0426347989465758)
(-39.19331453761631, -0.0255062545726498)
(-17.102740789047186, 0.0583704306894909)
(67.499787704256, 0.0148132358906579)
(-80.07314107293935, 0.012487608370541)
(89.5018675871561, -0.0111722538908926)
(-36.04502200337846, 0.027732411296845)
(-92.64459769368703, 0.0107933087887867)
(86.35905462806514, 0.0115787854311861)
(-26.590555025852712, -0.0375807705734432)
(-61.212033679168634, 0.016334477440491)
(249.7446034962173, 0.00400405842499421)
(-48.63297346021267, 0.0205578354154553)
(70.64335935242372, -0.0141541941579985)
(-64.35602244805503, -0.0155366857700825)
(-212.04335575261447, 0.00471596422453044)
(73.78676218647006, 0.0135513220378694)
(-95.7872531120814, -0.0104392335849293)
(45.48710878498235, -0.02197893994184)
(10.713010988255775, 0.0929394035698334)
(58.06778499217275, -0.0172186996097649)
(23.433689169693317, 0.0426347989465758)
(-70.64335935242372, -0.0141541941579985)
(-73.78676218647006, 0.0135513220378694)
(83.21614941630125, -0.012016030684702)
(3.870238580222165, 0.248692236445789)
(39.19331453761631, -0.0255062545726498)
(20.272001089138612, -0.0492692013251242)
(17.102740789047186, 0.0583704306894909)
(-20.272001089138612, -0.0492692013251242)
(61.212033679168634, 0.016334477440491)
(-7.443087053954458, -0.133143202113607)
(92.64459769368703, 0.0107933087887867)
(76.93001693732643, -0.0129977291788139)
(48.63297346021267, 0.0205578354154553)
(-51.77831782939038, -0.0193095024183706)
(-67.499787704256, 0.0148132358906579)
(-54.92323161043051, 0.0182042144946165)
(42.34060724053156, 0.0236114046136127)
(95.7872531120814, -0.0104392335849293)
(54.92323161043051, 0.0182042144946165)
(-86.35905462806514, 0.0115787854311861)
(-45.48710878498235, -0.02197893994184)
(29.744155513878802, 0.0336010649596176)
(-29.744155513878802, 0.0336010649596176)
(1148.2495022124986, 0.000870890532804869)
(64.35602244805503, -0.0155366857700825)
(80.07314107293935, 0.012487608370541)
(-58.06778499217275, -0.0172186996097649)
(13.920521426635718, -0.0716515891912541)
(32.89544020734542, -0.0303853130040648)
(-76.93001693732643, -0.0129977291788139)
(230.8940668237441, 0.0043309498383777)
(-32.89544020734542, -0.0303853130040648)
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=−13.9205214266357x2=−89.5018675871561x3=7.44308705395446x4=−83.2161494163012x5=26.5905550258527x6=51.7783178293904x7=−39.1933145376163x8=89.5018675871561x9=−26.5905550258527x10=70.6433593524237x11=−64.356022448055x12=−95.7872531120814x13=45.4871087849823x14=58.0677849921727x15=−70.6433593524237x16=83.2161494163012x17=39.1933145376163x18=20.2720010891386x19=−20.2720010891386x20=−7.44308705395446x21=76.9300169373264x22=−51.7783178293904x23=95.7872531120814x24=−45.4871087849823x25=64.356022448055x26=−58.0677849921727x27=13.9205214266357x28=32.8954402073454x29=−76.9300169373264x30=−32.8954402073454Puntos máximos de la función:
x30=−3.87023858022217x30=−98.9298409677395x30=36.0450220033785x30=−10.7130109882558x30=98.9298409677395x30=−42.3406072405316x30=−23.4336891696933x30=−17.1027407890472x30=67.499787704256x30=−80.0731410729394x30=−36.0450220033785x30=−92.644597693687x30=86.3590546280651x30=−61.2120336791686x30=249.744603496217x30=−48.6329734602127x30=−212.043355752614x30=73.7867621864701x30=10.7130109882558x30=23.4336891696933x30=−73.7867621864701x30=3.87023858022217x30=17.1027407890472x30=61.2120336791686x30=92.644597693687x30=48.6329734602127x30=−67.499787704256x30=−54.9232316104305x30=42.3406072405316x30=54.9232316104305x30=−86.3590546280651x30=29.7441555138788x30=−29.7441555138788x30=1148.2495022125x30=80.0731410729394x30=230.894066823744Decrece en los intervalos
[95.7872531120814,∞)Crece en los intervalos
(−∞,−95.7872531120814]