Para hallar los extremos hay que resolver la ecuación
$$\frac{d}{d x} f{\left(x \right)} = 0$$
(la derivada es igual a cero),
y las raíces de esta ecuación serán los extremos de esta función:
$$\frac{d}{d x} f{\left(x \right)} = $$
primera derivada$$- 5 \sin{\left(5 x \right)} - \frac{\sin{\left(\frac{x}{2} \right)}}{6} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = 99.9005796833491$$
$$x_{2} = 76.0286089176793$$
$$x_{3} = 8.16275737000355$$
$$x_{4} = 89.2173230918662$$
$$x_{5} = 272.696590280948$$
$$x_{6} = 42.1027250874331$$
$$x_{7} = -27.6396804726839$$
$$x_{8} = -43.9822971502571$$
$$x_{9} = -3.76356323495361$$
$$x_{10} = -37.6991118430775$$
$$x_{11} = -52.7724217014022$$
$$x_{12} = -77.9051629301206$$
$$x_{13} = 67.2354663161515$$
$$x_{14} = 5.02261883564151$$
$$x_{15} = -20.1101223930768$$
$$x_{16} = 64.0845818631479$$
$$x_{17} = 72.2499631677839$$
$$x_{18} = 33.9355486081239$$
$$x_{19} = -42.1027250874331$$
$$x_{20} = 26.3854700200704$$
$$x_{21} = 50.2654824574367$$
$$x_{22} = -65.980113590167$$
$$x_{23} = -45.8618692130811$$
$$x_{24} = -87.9645943005142$$
$$x_{25} = -32.0421914287363$$
$$x_{26} = -5.6569204143412$$
$$x_{27} = 40.2060510870431$$
$$x_{28} = 38.3294970746018$$
$$x_{29} = 48.3751221912863$$
$$x_{30} = 52.1558427235871$$
$$x_{31} = 77.9051629301206$$
$$x_{32} = 1.89036026615036$$
$$x_{33} = 60.3249138278303$$
$$x_{34} = 55.9224028717779$$
$$x_{35} = -25.7631264602426$$
$$x_{36} = 11.3136418230072$$
$$x_{37} = -99.9005796833491$$
$$x_{38} = -10.0594313703936$$
$$x_{39} = -33.9355486081239$$
$$x_{40} = 84.2010310655606$$
$$x_{41} = 94.2477796076938$$
$$x_{42} = -79.8018369305107$$
$$x_{43} = -54.0290456923903$$
$$x_{44} = -96.1273516705178$$
$$x_{45} = 96.1273516705178$$
$$x_{46} = 70.3756048505135$$
$$x_{47} = 6.28318530717959$$
$$x_{48} = -35.8087515769272$$
$$x_{49} = -64.0845818631479$$
$$x_{50} = 74.145494894803$$
$$x_{51} = 32.0421914287363$$
$$x_{52} = 61.5791242804438$$
$$x_{53} = 21.9844807103472$$
$$x_{54} = -55.9224028717779$$
$$x_{55} = 82.307673886173$$
$$x_{56} = -98.0240256709078$$
$$x_{57} = 23.8800124373663$$
$$x_{58} = -21.9844807103472$$
$$x_{59} = -69.7413032718138$$
$$x_{60} = -86.0742340343638$$
$$x_{61} = 28.2810017470895$$
$$x_{62} = 0$$
$$x_{63} = 65.980113590167$$
$$x_{64} = 62.2014678402716$$
$$x_{65} = -93.6215147148554$$
$$x_{66} = 45.8618692130811$$
$$x_{67} = 18.2232910287004$$
$$x_{68} = -71.6346604512014$$
$$x_{69} = -67.8544719074374$$
$$x_{70} = -47.7585432134711$$
$$x_{71} = -76.0286089176793$$
$$x_{72} = 16.3299338493128$$
$$x_{73} = -23.8800124373663$$
$$x_{74} = 11.9359853828349$$
$$x_{75} = -57.8092342361544$$
$$x_{76} = -13.8190994057112$$
$$x_{77} = -49.6350972259124$$
$$x_{78} = 10.0594313703936$$
$$x_{79} = -74.145494894803$$
$$x_{80} = 98.0240256709078$$
$$x_{81} = -15.7146311327303$$
$$x_{82} = -9.41811009598804$$
$$x_{83} = 20.1101223930768$$
$$x_{84} = 87.9645943005142$$
$$x_{85} = -84.8163337821431$$
$$x_{86} = -59.6835925534247$$
$$x_{87} = 43.9822971502571$$
$$x_{88} = -81.6814089933346$$
$$x_{89} = -1.89036026615036$$
$$x_{90} = 54.0290456923903$$
$$x_{91} = -39.5894721092279$$
$$x_{92} = -89.8549545666646$$
$$x_{93} = -91.7281575354678$$
$$x_{94} = -19.4758208143771$$
$$x_{95} = -11.9359853828349$$
$$x_{96} = 92.3682075448698$$
$$x_{97} = 86.0742340343638$$
$$x_{98} = 30.1553600643599$$
Signos de extremos en los puntos:
(99.90057968334914, -0.683034381241965)
(76.02860891767929, -0.683034381241964)
(8.162757370003554, -1.19629134322177)
(89.21732309186623, 1.2698637607974)
(272.6965902809482, 0.897497398652965)
(42.102725087433136, -1.19629134322177)
(-27.639680472683892, 1.1035076926828)
(-43.982297150257104, 0.666666666666667)
(-3.7635632349536086, 0.897497398652963)
(-37.69911184307752, 1.33333333333333)
(-52.77242170140224, 1.1035076926828)
(-77.90516293012058, 1.1035076926828)
(67.23546631615149, -1.19629134322177)
(5.022618835641509, 0.730520133233146)
(-20.110122393076836, 0.730520133233146)
(64.08458186314787, 1.2698637607974)
(72.2499631677839, -1.0005556049543)
(33.93554860812391, 0.897497398652963)
(-42.102725087433136, -1.19629134322177)
(26.38547002007036, 1.2698637607974)
(50.26548245743669, 1.33333333333333)
(-65.98011359016701, -1.0005556049543)
(-45.86186921308107, -1.19629134322177)
(-87.96459430051421, 1.33333333333333)
(-32.04219142873632, -1.31707172239489)
(-5.656920414341204, -1.31707172239489)
(40.206051087043065, 1.1035076926828)
(38.329497074601775, -0.683034381241965)
(48.37512219128633, -0.804435933553383)
(52.15584272358706, -0.804435933553383)
(77.90516293012058, 1.1035076926828)
(1.8903602661503636, -0.804435933553383)
(60.324913827830315, 1.1035076926828)
(55.9224028717779, -1.31707172239489)
(-25.7631264602426, -0.683034381241965)
(11.313641823007156, 1.2698637607974)
(-99.90057968334914, -0.683034381241965)
(-10.059431370393625, 1.1035076926828)
(-33.93554860812391, 0.897497398652963)
(84.2010310655606, 0.897497398652963)
(94.2477796076938, 0.666666666666667)
(-79.80183693051066, -1.19629134322177)
(-54.0290456923903, 0.897497398652963)
(-96.12735167051777, -1.19629134322177)
(96.12735167051777, -1.19629134322177)
(70.37560485051353, 0.730520133233146)
(6.283185307179586, 0.666666666666667)
(-35.80875157692716, -0.804435933553383)
(-64.08458186314787, 1.2698637607974)
(74.14549489480302, 1.2698637607974)
(32.04219142873632, -1.31707172239489)
(61.57912428044385, 1.2698637607974)
(21.98448071034721, -1.0005556049543)
(-55.9224028717779, -1.31707172239489)
(82.307673886173, -1.31707172239489)
(-98.02402567090783, 1.1035076926828)
(23.88001243736633, 1.2698637607974)
(-21.98448071034721, -1.0005556049543)
(-69.74130327181383, -1.31707172239489)
(-86.07423403436384, -0.804435933553383)
(28.281001747089483, -1.0005556049543)
(0, 4/3)
(65.98011359016701, -1.0005556049543)
(62.20146784027161, -0.683034381241965)
(-93.62151471485542, -1.31707172239489)
(45.86186921308107, -1.19629134322177)
(18.223291028700377, -1.31707172239489)
(-71.63466045120143, 0.897497398652964)
(-67.85447190743737, 0.730520133233145)
(-47.75854321347114, 1.1035076926828)
(-76.02860891767929, -0.683034381241964)
(16.32993384931278, 0.897497398652963)
(-23.88001243736633, 1.2698637607974)
(11.93598538283492, -0.683034381241965)
(-57.80923423615435, 0.730520133233146)
(-13.81909940571119, 1.2698637607974)
(-49.63509722591244, -0.683034381241965)
(10.059431370393625, 1.1035076926828)
(-74.14549489480302, 1.2698637607974)
(98.02402567090783, 1.1035076926828)
(-15.71463113273031, -1.0005556049543)
(-9.418110095988036, -1.0005556049543)
(20.110122393076836, 0.730520133233146)
(87.96459430051421, 1.33333333333333)
(-84.81633378214308, -1.0005556049543)
(-59.68359255342473, -1.0005556049543)
(43.982297150257104, 0.666666666666667)
(-81.68140899333463, 0.666666666666667)
(-1.8903602661503636, -0.804435933553383)
(54.0290456923903, 0.897497398652963)
(-39.589472109227884, -0.804435933553384)
(-89.85495456666457, -0.804435933553384)
(-91.72815753546782, 0.897497398652962)
(-19.47582081437714, -1.31707172239489)
(-11.93598538283492, -0.683034381241965)
(92.36820754486983, -1.19629134322177)
(86.07423403436384, -0.804435933553383)
(30.155360064359854, 0.730520133233146)
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:
$$x_{1} = 99.9005796833491$$
$$x_{2} = 76.0286089176793$$
$$x_{3} = 8.16275737000355$$
$$x_{4} = 42.1027250874331$$
$$x_{5} = 67.2354663161515$$
$$x_{6} = 72.2499631677839$$
$$x_{7} = -42.1027250874331$$
$$x_{8} = -65.980113590167$$
$$x_{9} = -45.8618692130811$$
$$x_{10} = -32.0421914287363$$
$$x_{11} = -5.6569204143412$$
$$x_{12} = 38.3294970746018$$
$$x_{13} = 48.3751221912863$$
$$x_{14} = 52.1558427235871$$
$$x_{15} = 1.89036026615036$$
$$x_{16} = 55.9224028717779$$
$$x_{17} = -25.7631264602426$$
$$x_{18} = -99.9005796833491$$
$$x_{19} = -79.8018369305107$$
$$x_{20} = -96.1273516705178$$
$$x_{21} = 96.1273516705178$$
$$x_{22} = -35.8087515769272$$
$$x_{23} = 32.0421914287363$$
$$x_{24} = 21.9844807103472$$
$$x_{25} = -55.9224028717779$$
$$x_{26} = 82.307673886173$$
$$x_{27} = -21.9844807103472$$
$$x_{28} = -69.7413032718138$$
$$x_{29} = -86.0742340343638$$
$$x_{30} = 28.2810017470895$$
$$x_{31} = 65.980113590167$$
$$x_{32} = 62.2014678402716$$
$$x_{33} = -93.6215147148554$$
$$x_{34} = 45.8618692130811$$
$$x_{35} = 18.2232910287004$$
$$x_{36} = -76.0286089176793$$
$$x_{37} = 11.9359853828349$$
$$x_{38} = -49.6350972259124$$
$$x_{39} = -15.7146311327303$$
$$x_{40} = -9.41811009598804$$
$$x_{41} = -84.8163337821431$$
$$x_{42} = -59.6835925534247$$
$$x_{43} = -1.89036026615036$$
$$x_{44} = -39.5894721092279$$
$$x_{45} = -89.8549545666646$$
$$x_{46} = -19.4758208143771$$
$$x_{47} = -11.9359853828349$$
$$x_{48} = 92.3682075448698$$
$$x_{49} = 86.0742340343638$$
Puntos máximos de la función:
$$x_{49} = 89.2173230918662$$
$$x_{49} = 272.696590280948$$
$$x_{49} = -27.6396804726839$$
$$x_{49} = -43.9822971502571$$
$$x_{49} = -3.76356323495361$$
$$x_{49} = -37.6991118430775$$
$$x_{49} = -52.7724217014022$$
$$x_{49} = -77.9051629301206$$
$$x_{49} = 5.02261883564151$$
$$x_{49} = -20.1101223930768$$
$$x_{49} = 64.0845818631479$$
$$x_{49} = 33.9355486081239$$
$$x_{49} = 26.3854700200704$$
$$x_{49} = 50.2654824574367$$
$$x_{49} = -87.9645943005142$$
$$x_{49} = 40.2060510870431$$
$$x_{49} = 77.9051629301206$$
$$x_{49} = 60.3249138278303$$
$$x_{49} = 11.3136418230072$$
$$x_{49} = -10.0594313703936$$
$$x_{49} = -33.9355486081239$$
$$x_{49} = 84.2010310655606$$
$$x_{49} = 94.2477796076938$$
$$x_{49} = -54.0290456923903$$
$$x_{49} = 70.3756048505135$$
$$x_{49} = 6.28318530717959$$
$$x_{49} = -64.0845818631479$$
$$x_{49} = 74.145494894803$$
$$x_{49} = 61.5791242804438$$
$$x_{49} = -98.0240256709078$$
$$x_{49} = 23.8800124373663$$
$$x_{49} = 0$$
$$x_{49} = -71.6346604512014$$
$$x_{49} = -67.8544719074374$$
$$x_{49} = -47.7585432134711$$
$$x_{49} = 16.3299338493128$$
$$x_{49} = -23.8800124373663$$
$$x_{49} = -57.8092342361544$$
$$x_{49} = -13.8190994057112$$
$$x_{49} = 10.0594313703936$$
$$x_{49} = -74.145494894803$$
$$x_{49} = 98.0240256709078$$
$$x_{49} = 20.1101223930768$$
$$x_{49} = 87.9645943005142$$
$$x_{49} = 43.9822971502571$$
$$x_{49} = -81.6814089933346$$
$$x_{49} = 54.0290456923903$$
$$x_{49} = -91.7281575354678$$
$$x_{49} = 30.1553600643599$$
Decrece en los intervalos
$$\left[99.9005796833491, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -99.9005796833491\right]$$