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)+2cos(x)=0Resolvermos esta ecuaciónRaíces de esta ecuación
x1=69.1439554764926x2=−1.0768739863118x3=−47.1662676027767x4=15.8336114149477x5=25.2119030642106x6=18.954681766529x7=1.0768739863118x8=−18.954681766529x9=−84.8465692433091x10=−25.2119030642106x11=34.6152330552306x12=−40.8895777660408x13=62.863657228703x14=−81.7058821480364x15=44.0276918992479x16=−66.0037377708277x17=100.550852725424x18=31.479374920314x19=−91.1281305511393x20=−100.550852725424x21=40.8895777660408x22=91.1281305511393x23=−59.7237354324305x24=−97.4099011706723x25=66.0037377708277x26=−34.6152330552306x27=12.7222987717666x28=81.7058821480364x29=−53.4444796697636x30=50.3052188363296x31=−62.863657228703x32=−31.479374920314x33=−9.62956034329743x34=−78.5652673845995x35=−50.3052188363296x36=−94.2689923093066x37=−28.3447768697864x38=28.3447768697864x39=84.8465692433091x40=47.1662676027767x41=−69.1439554764926x42=78.5652673845995x43=−6.57833373272234x44=−44.0276918992479x45=9.62956034329743x46=75.4247339745236x47=−75.4247339745236x48=6.57833373272234x49=−128.820822990274x50=−72.2842925036825x51=−37.7520396346102x52=87.9873209346887x53=72.2842925036825x54=97.4099011706723x55=3.6435971674254x56=59.7237354324305x57=53.4444796697636x58=−3.6435971674254x59=−22.0814757672807x60=94.2689923093066x61=−56.5839987378634x62=−12.7222987717666x63=−87.9873209346887x64=56.5839987378634x65=−15.8336114149477x66=37.7520396346102x67=22.0814757672807Signos de extremos en los puntos:
(69.1439554764926, 69.1439615216012)
(-1.0768739863118038, -1.39100784545588)
(-47.1662676027767, 47.1662866291145)
(15.833611414947718, -15.834107331638)
(25.21190306421058, 25.2120270830452)
(18.954681766529042, 18.9549722147554)
(1.0768739863118038, 1.39100784545588)
(-18.954681766529042, -18.9549722147554)
(-84.84656924330915, 84.8465725158561)
(-25.21190306421058, -25.2120270830452)
(34.61523305523058, -34.6152811148717)
(-40.889577766040844, 40.8896069506711)
(62.863657228703005, 62.8636652712142)
(-81.70588214803641, -81.7058858124955)
(44.02769189924788, 44.0277152852979)
(-66.00373777082767, 66.0037447198836)
(100.55085272542402, 100.550854691956)
(31.479374920314047, 31.4794387763188)
(-91.1281305511393, 91.1281331927175)
(-100.55085272542402, -100.550854691956)
(40.889577766040844, -40.8896069506711)
(91.1281305511393, -91.1281331927175)
(-59.72373543243046, 59.7237448102597)
(-97.40990117067226, 97.4099033335782)
(66.00373777082767, -66.0037447198836)
(-34.61523305523058, 34.6152811148717)
(12.722298771766635, 12.7232465674385)
(81.70588214803641, 81.7058858124955)
(-53.44447966976355, 53.4444927529527)
(50.30521883632959, 50.3052345220647)
(-62.863657228703005, -62.8636652712142)
(-31.479374920314047, -31.4794387763188)
(-9.62956034329743, 9.63170728857969)
(-78.56526738459954, 78.5652715061143)
(-50.30521883632959, -50.3052345220647)
(-94.26899230930657, -94.2689946956226)
(-28.344776869786372, 28.3448642580985)
(28.344776869786372, -28.3448642580985)
(84.84656924330915, -84.8465725158561)
(47.1662676027767, -47.1662866291145)
(-69.1439554764926, -69.1439615216012)
(78.56526738459954, -78.5652715061143)
(-6.578333732722339, -6.58476172355643)
(-44.02769189924788, -44.0277152852979)
(9.62956034329743, -9.63170728857969)
(75.4247339745236, 75.4247386323507)
(-75.4247339745236, -75.4247386323507)
(6.578333732722339, 6.58476172355643)
(-128.8208229902735, 128.820823925608)
(-72.2842925036825, 72.2842977950245)
(-37.75203963461023, -37.7520767019434)
(87.9873209346887, 87.9873238692648)
(72.2842925036825, -72.2842977950245)
(97.40990117067226, -97.4099033335782)
(3.643597167425401, -3.67523306366032)
(59.72373543243046, -59.7237448102597)
(53.44447966976355, -53.4444927529527)
(-3.643597167425401, 3.67523306366032)
(-22.081475767280747, 22.0816600122592)
(94.26899230930657, 94.2689946956226)
(-56.58399873786344, -56.5840097635798)
(-12.722298771766635, -12.7232465674385)
(-87.9873209346887, -87.9873238692648)
(56.58399873786344, 56.5840097635798)
(-15.833611414947718, 15.834107331638)
(37.75203963461023, 37.7520767019434)
(22.081475767280747, -22.0816600122592)
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=−1.0768739863118x2=15.8336114149477x3=−18.954681766529x4=−25.2119030642106x5=34.6152330552306x6=−81.7058821480364x7=−100.550852725424x8=40.8895777660408x9=91.1281305511393x10=66.0037377708277x11=−62.863657228703x12=−31.479374920314x13=−50.3052188363296x14=−94.2689923093066x15=28.3447768697864x16=84.8465692433091x17=47.1662676027767x18=−69.1439554764926x19=78.5652673845995x20=−6.57833373272234x21=−44.0276918992479x22=9.62956034329743x23=−75.4247339745236x24=−37.7520396346102x25=72.2842925036825x26=97.4099011706723x27=3.6435971674254x28=59.7237354324305x29=53.4444796697636x30=−56.5839987378634x31=−12.7222987717666x32=−87.9873209346887x33=22.0814757672807Puntos máximos de la función:
x33=69.1439554764926x33=−47.1662676027767x33=25.2119030642106x33=18.954681766529x33=1.0768739863118x33=−84.8465692433091x33=−40.8895777660408x33=62.863657228703x33=44.0276918992479x33=−66.0037377708277x33=100.550852725424x33=31.479374920314x33=−91.1281305511393x33=−59.7237354324305x33=−97.4099011706723x33=−34.6152330552306x33=12.7222987717666x33=81.7058821480364x33=−53.4444796697636x33=50.3052188363296x33=−9.62956034329743x33=−78.5652673845995x33=−28.3447768697864x33=75.4247339745236x33=6.57833373272234x33=−128.820822990274x33=−72.2842925036825x33=87.9873209346887x33=−3.6435971674254x33=−22.0814757672807x33=94.2689923093066x33=56.5839987378634x33=−15.8336114149477x33=37.7520396346102Decrece en los intervalos
[97.4099011706723,∞)Crece en los intervalos
(−∞,−100.550852725424]