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)−x2cos(x)+1=0Resolvermos esta ecuaciónRaíces de esta ecuación
x1=−50.2256674407532x2=−87.941852980689x3=25.0529526753384x4=84.8230016469244x5=47.1238898038469x6=100.511067265113x7=−53.4070751110265x8=−37.6459978360151x9=91.106186954104x10=−84.8230016469244x11=5.95017264337656x12=−3.14159265358979x13=−69.086091013299x14=87.941852980689x15=−279.601746169492x16=−40.8407044966673x17=62.8000086337252x18=−62.8000086337252x19=−100.511067265113x20=−12.4054996335861x21=78.5398163397448x22=477.51789502706x23=−18.7429502117119x24=−9.42477796076938x25=94.2265549654551x26=72.2566310325652x27=56.5132815466599x28=9.42477796076938x29=43.9367850637406x30=40.8407044966673x31=59.6902604182061x32=−25.0529526753384x33=−91.106186954104x34=97.3893722612836x35=34.5575191894877x36=75.3716900810604x37=−78.5398163397448x38=37.6459978360151x39=31.3521566903887x40=779.112411068009x41=81.6569174978428x42=−65.9734457253857x43=−43.9367850637406x44=12.4054996335861x45=3.14159265358979x46=15.707963267949x47=−31.3521566903887x48=−21.9911485751286x49=18.7429502117119x50=−15.707963267949x51=69.086091013299x52=128.805298797182x53=−94.2265549654551x54=28.2743338823081x55=−59.6902604182061x56=−408.402147842567x57=−81.6569174978428x58=−97.3893722612836x59=21.9911485751286x60=65.9734457253857x61=−34.5575191894877x62=−72.2566310325652x63=50.2256674407532x64=−75.3716900810604x65=−28.2743338823081x66=−56.5132815466599x67=−5.95017264337656x68=53.4070751110265x69=−47.1238898038469Signos de extremos en los puntos:
(-50.22566744075319, -0.0398044981539202)
(-87.94185298068903, -0.022739359696793)
(25.0529526753384, 0.0797039218326035)
(84.82300164692441, 0)
(47.1238898038469, 0)
(100.51106726511297, 0.0198963368185454)
(-53.40707511102649, 0)
(-37.645997836015106, -0.0530890372838442)
(91.106186954104, 0)
(-84.82300164692441, 0)
(5.9501726433765585, 0.326891661078669)
(-3.141592653589793, 0)
(-69.08609101329898, -0.028943323105097)
(87.94185298068903, 0.022739359696793)
(-279.6017461694916, 0)
(-40.840704496667314, 0)
(62.80000863372525, 0.0318390562713079)
(-62.80000863372525, -0.0318390562713079)
(-100.51106726511297, -0.0198963368185454)
(-12.405499633586086, -0.160178002058028)
(78.53981633974483, 0)
(477.5178950270596, 0.00418830634377207)
(-18.742950211711907, -0.106403899511075)
(-9.42477796076938, 0)
(94.22655496545507, 0.0212230487092482)
(72.25663103256524, 0)
(56.51328154665989, 0.0353788334069361)
(9.42477796076938, 0)
(43.936785063740594, 0.0454963762334591)
(40.840704496667314, 0)
(59.69026041820607, 0)
(-25.0529526753384, -0.0797039218326035)
(-91.106186954104, 0)
(97.3893722612836, 0)
(34.55751918948773, 0)
(75.37169008106044, 0.026530491785468)
(-78.53981633974483, 0)
(37.645997836015106, 0.0530890372838442)
(31.352156690388735, 0.0637266332931457)
(779.1124110680094, 0.0025670194400556)
(81.6569174978428, 0.0244890470959608)
(-65.97344572538566, 0)
(-43.936785063740594, -0.0454963762334591)
(12.405499633586086, 0.160178002058028)
(3.141592653589793, 0)
(15.707963267948966, 0)
(-31.352156690388735, -0.0637266332931457)
(-21.991148575128552, 0)
(18.742950211711907, 0.106403899511075)
(-15.707963267948966, 0)
(69.08609101329898, 0.028943323105097)
(128.80529879718154, 0)
(-94.22655496545507, -0.0212230487092482)
(28.274333882308138, 0)
(-59.69026041820607, 0)
(-408.4021478425674, -0.00489710453208163)
(-81.6569174978428, -0.0244890470959608)
(-97.3893722612836, 0)
(21.991148575128552, 0)
(65.97344572538566, 0)
(-34.55751918948773, 0)
(-72.25663103256524, 0)
(50.22566744075319, 0.0398044981539202)
(-75.37169008106044, -0.026530491785468)
(-28.274333882308138, 0)
(-56.51328154665989, -0.0353788334069361)
(-5.9501726433765585, -0.326891661078669)
(53.40707511102649, 0)
(-47.1238898038469, 0)
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=−50.2256674407532x2=−87.941852980689x3=84.8230016469244x4=47.1238898038469x5=−37.6459978360151x6=91.106186954104x7=−69.086091013299x8=−62.8000086337252x9=−100.511067265113x10=−12.4054996335861x11=78.5398163397448x12=−18.7429502117119x13=72.2566310325652x14=9.42477796076938x15=40.8407044966673x16=59.6902604182061x17=−25.0529526753384x18=97.3893722612836x19=34.5575191894877x20=−43.9367850637406x21=3.14159265358979x22=15.707963267949x23=−31.3521566903887x24=128.805298797182x25=−94.2265549654551x26=28.2743338823081x27=−408.402147842567x28=−81.6569174978428x29=21.9911485751286x30=65.9734457253857x31=−75.3716900810604x32=−56.5132815466599x33=−5.95017264337656x34=53.4070751110265Puntos máximos de la función:
x34=25.0529526753384x34=100.511067265113x34=−53.4070751110265x34=−84.8230016469244x34=5.95017264337656x34=−3.14159265358979x34=87.941852980689x34=−279.601746169492x34=−40.8407044966673x34=62.8000086337252x34=477.51789502706x34=−9.42477796076938x34=94.2265549654551x34=56.5132815466599x34=43.9367850637406x34=−91.106186954104x34=75.3716900810604x34=−78.5398163397448x34=37.6459978360151x34=31.3521566903887x34=779.112411068009x34=81.6569174978428x34=−65.9734457253857x34=12.4054996335861x34=−21.9911485751286x34=18.7429502117119x34=−15.707963267949x34=69.086091013299x34=−59.6902604182061x34=−97.3893722612836x34=−34.5575191894877x34=−72.2566310325652x34=50.2256674407532x34=−28.2743338823081x34=−47.1238898038469Decrece en los intervalos
[128.805298797182,∞)Crece en los intervalos
(−∞,−408.402147842567]