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−x3sin(x)+3x2cos(x)=0Resolvermos esta ecuaciónRaíces de esta ecuación
x1=−28.3796522911214x2=−72.2981021067071x3=−40.913898225293x4=−62.8795272030449x5=97.4201569811411x6=34.6438990396267x7=−9.72402747617551x8=−47.1873806732917x9=78.5779764426249x10=59.7404355133729x11=−50.325024483292x12=72.2981021067071x13=−91.1390917936668x14=69.1583898858035x15=3.80876221919969x16=47.1873806732917x17=−6.70395577578075x18=−44.0502961191214x19=100.560788770886x20=−19.0061082873963x21=−81.7181040853573x22=37.7783560989567x23=66.0188560490172x24=−25.2509941253717x25=44.0502961191214x26=56.6016202331048x27=91.1390917936668x28=1.19245882933643x29=87.9986725257711x30=−94.2795891235637x31=81.7181040853573x32=−12.7966483902814x33=40.913898225293x34=31.510845756676x35=19.0061082873963x36=−56.6016202331048x37=−59.7404355133729x38=−87.9986725257711x39=−75.4379705139506x40=28.3796522911214x41=−66.0188560490172x42=0x43=−34.6438990396267x44=−37.7783560989567x45=−97.4201569811411x46=−3.80876221919969x47=25.2509941253717x48=−84.8583399660622x49=15.8945130636842x50=−100.560788770886x51=75.4379705139506x52=9.72402747617551x53=−15.8945130636842x54=−31.510845756676x55=6.70395577578075x56=−1.19245882933643x57=−22.12591435735x58=−69.1583898858035x59=−53.4631297645908x60=62.8795272030449x61=22.12591435735x62=53.4631297645908x63=12.7966483902814x64=94.2795891235637x65=50.325024483292x66=84.8583399660622x67=−78.5779764426249Signos de extremos en los puntos:
(-28.37965229112142, 22730.4563261038)
(-72.29810210670713, 377578.383339478)
(-40.91389822529297, 68304.326534245)
(-62.87952720304487, -248332.79602616)
(97.42015698114113, -924146.136898602)
(34.64389903962671, -41424.5724319187)
(-9.72402747617551, 878.608875900237)
(-47.18738067329166, 104858.027361626)
(78.57797644262494, -484826.373587257)
(59.74043551337287, -212940.488750329)
(-50.32502448329199, -127227.703282192)
(72.29810210670713, -377578.383339478)
(-91.13909179366682, 756621.948790976)
(69.15838988580347, 330465.705562301)
(3.808762219199689, -43.4050129540828)
(47.18738067329166, -104858.027361626)
(-6.703955775780748, -275.015342086354)
(-44.05029611912139, -85278.9144731517)
(100.56078877088648, 1016465.96298217)
(-19.006108287396344, -6781.65561120486)
(-81.71810408535728, -545333.761493627)
(37.77835609895673, 53748.2253256845)
(66.01885604901719, -287445.855707585)
(-25.25099412537165, -15987.9141234403)
(44.05029611912139, 85278.9144731517)
(56.60162023310481, 181082.896088805)
(91.13909179366682, -756621.948790976)
(1.1924588293364287, 0.626323798219316)
(87.99867252577111, 681045.511399255)
(-94.27958912356374, -837593.47806229)
(81.71810408535728, 545333.761493627)
(-12.796648390281426, -2040.19006584704)
(40.91389822529297, -68304.326534245)
(31.51084575667604, 31147.3291476214)
(19.006108287396344, 6781.65561120486)
(-56.60162023310481, -181082.896088805)
(-59.74043551337287, 212940.488750329)
(-87.99867252577111, -681045.511399255)
(-75.43797051395065, -428969.926773577)
(28.37965229112142, -22730.4563261038)
(-66.01885604901719, 287445.855707585)
(0, 0)
(-34.64389903962671, 41424.5724319187)
(-37.77835609895673, -53748.2253256845)
(-97.42015698114113, 924146.136898602)
(-3.808762219199689, 43.4050129540828)
(25.25099412537165, 15987.9141234403)
(-84.85833996606219, 610678.128197996)
(15.894513063684203, -3945.84968737938)
(-100.56078877088648, -1016465.96298217)
(75.43797051395065, 428969.926773577)
(9.72402747617551, -878.608875900237)
(-15.894513063684203, 3945.84968737938)
(-31.51084575667604, -31147.3291476214)
(6.703955775780748, 275.015342086354)
(-1.1924588293364287, -0.626323798219316)
(-22.125914357349984, 10733.6615463961)
(-69.15838988580347, -330465.705562301)
(-53.463129764590846, 152573.980219896)
(62.87952720304487, 248332.79602616)
(22.125914357349984, -10733.6615463961)
(53.463129764590846, -152573.980219896)
(12.796648390281426, 2040.19006584704)
(94.27958912356374, 837593.47806229)
(50.32502448329199, 127227.703282192)
(84.85833996606219, -610678.128197996)
(-78.57797644262494, 484826.373587257)
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=−62.8795272030449x2=97.4201569811411x3=34.6438990396267x4=78.5779764426249x5=59.7404355133729x6=−50.325024483292x7=72.2981021067071x8=3.80876221919969x9=47.1873806732917x10=−6.70395577578075x11=−44.0502961191214x12=−19.0061082873963x13=−81.7181040853573x14=66.0188560490172x15=−25.2509941253717x16=91.1390917936668x17=−94.2795891235637x18=−12.7966483902814x19=40.913898225293x20=−56.6016202331048x21=−87.9986725257711x22=−75.4379705139506x23=28.3796522911214x24=−37.7783560989567x25=15.8945130636842x26=−100.560788770886x27=9.72402747617551x28=−31.510845756676x29=−1.19245882933643x30=−69.1583898858035x31=22.12591435735x32=53.4631297645908x33=84.8583399660622Puntos máximos de la función:
x33=−28.3796522911214x33=−72.2981021067071x33=−40.913898225293x33=−9.72402747617551x33=−47.1873806732917x33=−91.1390917936668x33=69.1583898858035x33=100.560788770886x33=37.7783560989567x33=44.0502961191214x33=56.6016202331048x33=1.19245882933643x33=87.9986725257711x33=81.7181040853573x33=31.510845756676x33=19.0061082873963x33=−59.7404355133729x33=−66.0188560490172x33=−34.6438990396267x33=−97.4201569811411x33=−3.80876221919969x33=25.2509941253717x33=−84.8583399660622x33=75.4379705139506x33=−15.8945130636842x33=6.70395577578075x33=−22.12591435735x33=−53.4631297645908x33=62.8795272030449x33=12.7966483902814x33=94.2795891235637x33=50.325024483292x33=−78.5779764426249Decrece en los intervalos
[97.4201569811411,∞)Crece en los intervalos
(−∞,−100.560788770886]