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−log(x)sin(x)+xcos(x)=0Resolvermos esta ecuaciónRaíces de esta ecuación
x1=62.8356966541501x2=75.4012916642681x3=28.2849113047725x4=47.1293968198114x5=59.6943570030875x6=31.4251563350128x7=50.27056033759x8=9.47170218677955x9=100.533122377741x10=43.9883049460921x11=84.8256564376189x12=15.7310277752208x13=37.7064180281721x14=97.3916147574604x15=12.5976921976804x16=1.27285069827148x17=91.1086195251935x18=81.6841895128946x19=40.8473034495909x20=72.2598642156451x21=65.9770636783598x22=3.37991614208723x23=34.5656848442796x24=22.0058475927713x25=18.8675971617309x26=69.1184539759405x27=25.1450734377105x28=6.36781151369107x29=53.4117815402062x30=94.2501135627054x31=78.5427340593526x32=56.5530498251275x33=87.967133489911Signos de extremos en los puntos:
(62.835696654150134, 4.14049274584816)
(75.40129166426813, 4.32280406143887)
(28.284911304772503, -3.34214152179011)
(47.1293968198114, -3.85283851894378)
(59.69435700308747, -4.08920318061012)
(31.425156335012787, 3.44746188086714)
(50.27056033759003, 3.91736911923955)
(9.471702186779549, -2.24583383410247)
(100.53312237774094, 4.61047651900993)
(43.98830494609213, 3.78385551437724)
(84.82565643761893, -4.44058240090197)
(15.731027775220827, -2.7549021263166)
(37.70641802817207, 3.62973343908044)
(97.39161475746043, -4.57872860340226)
(12.597692197680386, 2.53227099874907)
(1.2728506982714773, 0.0708232692475832)
(91.10861952519349, -4.5120390660658)
(81.68418951289463, 4.40284344444233)
(40.847303449590925, -3.70976003369716)
(72.25986421564514, -4.28024647479203)
(65.9770636783598, -4.18927974348899)
(3.3799161420872266, -1.18342849059061)
(34.56568484427963, -3.54274330777479)
(22.00584759277127, -3.09097426796676)
(18.86759716173087, 2.93696797853021)
(69.11845397594048, 4.23579704883419)
(25.14507343771052, 3.22441678455125)
(6.367811513691074, 1.8446308321891)
(53.41178154020617, -3.9779872921632)
(94.25011356270541, 4.54593964955556)
(78.5427340593526, -4.3636242855634)
(56.553049825127495, 4.03514038997721)
(87.96713348991098, 4.4769488290828)
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=28.2849113047725x2=47.1293968198114x3=59.6943570030875x4=9.47170218677955x5=84.8256564376189x6=15.7310277752208x7=97.3916147574604x8=91.1086195251935x9=40.8473034495909x10=72.2598642156451x11=65.9770636783598x12=3.37991614208723x13=34.5656848442796x14=22.0058475927713x15=53.4117815402062x16=78.5427340593526Puntos máximos de la función:
x16=62.8356966541501x16=75.4012916642681x16=31.4251563350128x16=50.27056033759x16=100.533122377741x16=43.9883049460921x16=37.7064180281721x16=12.5976921976804x16=1.27285069827148x16=81.6841895128946x16=18.8675971617309x16=69.1184539759405x16=25.1450734377105x16=6.36781151369107x16=94.2501135627054x16=56.5530498251275x16=87.967133489911Decrece en los intervalos
[97.3916147574604,∞)Crece en los intervalos
(−∞,3.37991614208723]