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$$\frac{\frac{1}{x \sin{\left(x \right)}} \left(- x \cos{\left(x \right)} - \sin{\left(x \right)}\right)}{x \sin{\left(x \right)}} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = -64.4181717218392$$
$$x_{2} = 51.855560729152$$
$$x_{3} = -58.1366632448992$$
$$x_{4} = 26.7409160147873$$
$$x_{5} = -17.3363779239834$$
$$x_{6} = -61.2773745335697$$
$$x_{7} = -42.4350618814099$$
$$x_{8} = 29.8785865061074$$
$$x_{9} = -80.1230928148503$$
$$x_{10} = -2.02875783811043$$
$$x_{11} = -33.0170010333572$$
$$x_{12} = 73.8409691490209$$
$$x_{13} = 64.4181717218392$$
$$x_{14} = 89.5465575382492$$
$$x_{15} = -20.469167402741$$
$$x_{16} = -26.7409160147873$$
$$x_{17} = -36.1559664195367$$
$$x_{18} = 33.0170010333572$$
$$x_{19} = 20.469167402741$$
$$x_{20} = 54.9960525574964$$
$$x_{21} = 7.97866571241324$$
$$x_{22} = -14.2074367251912$$
$$x_{23} = 39.295350981473$$
$$x_{24} = 36.1559664195367$$
$$x_{25} = 83.2642147040886$$
$$x_{26} = 86.4053708116885$$
$$x_{27} = -92.687771772017$$
$$x_{28} = -29.8785865061074$$
$$x_{29} = -67.5590428388084$$
$$x_{30} = 76.9820093304187$$
$$x_{31} = -11.085538406497$$
$$x_{32} = 70.69997803861$$
$$x_{33} = -51.855560729152$$
$$x_{34} = 48.7152107175577$$
$$x_{35} = 17.3363779239834$$
$$x_{36} = -4.91318043943488$$
$$x_{37} = -86.4053708116885$$
$$x_{38} = 92.687771772017$$
$$x_{39} = -39.295350981473$$
$$x_{40} = -73.8409691490209$$
$$x_{41} = 80.1230928148503$$
$$x_{42} = 58.1366632448992$$
$$x_{43} = -45.57503179559$$
$$x_{44} = 67.5590428388084$$
$$x_{45} = -89.5465575382492$$
$$x_{46} = -70.69997803861$$
$$x_{47} = 95.8290108090195$$
$$x_{48} = 11.085538406497$$
$$x_{49} = -95.8290108090195$$
$$x_{50} = 98.9702722883957$$
$$x_{51} = 2.02875783811043$$
$$x_{52} = -83.2642147040886$$
$$x_{53} = 4.91318043943488$$
$$x_{54} = -23.6042847729804$$
$$x_{55} = -48.7152107175577$$
$$x_{56} = -76.9820093304187$$
$$x_{57} = 61.2773745335697$$
$$x_{58} = 42.4350618814099$$
$$x_{59} = -54.9960525574964$$
$$x_{60} = -7.97866571241324$$
$$x_{61} = -98.9702722883957$$
$$x_{62} = 23.6042847729804$$
$$x_{63} = 45.57503179559$$
$$x_{64} = 14.2074367251912$$
Signos de extremos en los puntos:
(-64.41817172183916, 0.0155254403629104)
(51.85556072915197, 0.0192879203587517)
(-58.13666324489916, 0.0172033940004342)
(26.74091601478731, 0.0374220157962705)
(-17.33637792398336, -0.0577780571919075)
(-61.277374533569656, -0.0163214099412236)
(-42.43506188140989, -0.0235719610527759)
(29.878586506107393, -0.0334875253498635)
(-80.12309281485025, -0.012481768326346)
(-2.028757838110434, 0.549539399355154)
(-33.017001033357246, 0.0303013153120829)
(73.8409691490209, -0.0135438593041987)
(64.41817172183916, 0.0155254403629104)
(89.54655753824919, 0.0111680714555952)
(-20.46916740274095, 0.0489122309705376)
(-26.74091601478731, 0.0374220157962705)
(-36.15596641953672, -0.0276685290732083)
(33.017001033357246, 0.0303013153120829)
(20.46916740274095, 0.0489122309705376)
(54.99605255749639, -0.0181861288731106)
(7.978665712413241, 0.126314820892896)
(-14.207436725191188, 0.0705598082559851)
(39.295350981472986, 0.0254565420761017)
(36.15596641953672, -0.0276685290732083)
(83.26421470408864, 0.0120108274669912)
(86.40537081168854, -0.0115741297055022)
(-92.687771772017, -0.010789537599982)
(-29.878586506107393, -0.0334875253498635)
(-67.5590428388084, -0.0148034889130555)
(76.98200933041872, 0.0129911439804425)
(-11.085538406497022, -0.090573901470554)
(70.69997803861, 0.0141456907486248)
(-51.85556072915197, 0.0192879203587517)
(48.715210717557724, -0.0205317939012932)
(17.33637792398336, -0.0577780571919075)
(-4.913180439434884, -0.207707187480149)
(-86.40537081168854, -0.0115741297055022)
(92.687771772017, -0.010789537599982)
(-39.295350981472986, 0.0254565420761017)
(-73.8409691490209, -0.0135438593041987)
(80.12309281485025, -0.012481768326346)
(58.13666324489916, 0.0172033940004342)
(-45.57503179559002, 0.021947120029759)
(67.5590428388084, -0.0148034889130555)
(-89.54655753824919, 0.0111680714555952)
(-70.69997803861, 0.0141456907486248)
(95.82901080901948, 0.010435821442073)
(11.085538406497022, -0.090573901470554)
(-95.82901080901948, 0.010435821442073)
(98.9702722883957, -0.0101045598989274)
(2.028757838110434, 0.549539399355154)
(-83.26421470408864, 0.0120108274669912)
(4.913180439434884, -0.207707187480149)
(-23.604284772980407, -0.0424031912834926)
(-48.715210717557724, -0.0205317939012932)
(-76.98200933041872, 0.0129911439804425)
(61.277374533569656, -0.0163214099412236)
(42.43506188140989, -0.0235719610527759)
(-54.99605255749639, -0.0181861288731106)
(-7.978665712413241, 0.126314820892896)
(-98.9702722883957, -0.0101045598989274)
(23.604284772980407, -0.0424031912834926)
(45.57503179559002, 0.021947120029759)
(14.207436725191188, 0.0705598082559851)
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:
$$x_{1} = -64.4181717218392$$
$$x_{2} = 51.855560729152$$
$$x_{3} = -58.1366632448992$$
$$x_{4} = 26.7409160147873$$
$$x_{5} = -2.02875783811043$$
$$x_{6} = -33.0170010333572$$
$$x_{7} = 64.4181717218392$$
$$x_{8} = 89.5465575382492$$
$$x_{9} = -20.469167402741$$
$$x_{10} = -26.7409160147873$$
$$x_{11} = 33.0170010333572$$
$$x_{12} = 20.469167402741$$
$$x_{13} = 7.97866571241324$$
$$x_{14} = -14.2074367251912$$
$$x_{15} = 39.295350981473$$
$$x_{16} = 83.2642147040886$$
$$x_{17} = 76.9820093304187$$
$$x_{18} = 70.69997803861$$
$$x_{19} = -51.855560729152$$
$$x_{20} = -39.295350981473$$
$$x_{21} = 58.1366632448992$$
$$x_{22} = -45.57503179559$$
$$x_{23} = -89.5465575382492$$
$$x_{24} = -70.69997803861$$
$$x_{25} = 95.8290108090195$$
$$x_{26} = -95.8290108090195$$
$$x_{27} = 2.02875783811043$$
$$x_{28} = -83.2642147040886$$
$$x_{29} = -76.9820093304187$$
$$x_{30} = -7.97866571241324$$
$$x_{31} = 45.57503179559$$
$$x_{32} = 14.2074367251912$$
Puntos máximos de la función:
$$x_{32} = -17.3363779239834$$
$$x_{32} = -61.2773745335697$$
$$x_{32} = -42.4350618814099$$
$$x_{32} = 29.8785865061074$$
$$x_{32} = -80.1230928148503$$
$$x_{32} = 73.8409691490209$$
$$x_{32} = -36.1559664195367$$
$$x_{32} = 54.9960525574964$$
$$x_{32} = 36.1559664195367$$
$$x_{32} = 86.4053708116885$$
$$x_{32} = -92.687771772017$$
$$x_{32} = -29.8785865061074$$
$$x_{32} = -67.5590428388084$$
$$x_{32} = -11.085538406497$$
$$x_{32} = 48.7152107175577$$
$$x_{32} = 17.3363779239834$$
$$x_{32} = -4.91318043943488$$
$$x_{32} = -86.4053708116885$$
$$x_{32} = 92.687771772017$$
$$x_{32} = -73.8409691490209$$
$$x_{32} = 80.1230928148503$$
$$x_{32} = 67.5590428388084$$
$$x_{32} = 11.085538406497$$
$$x_{32} = 98.9702722883957$$
$$x_{32} = 4.91318043943488$$
$$x_{32} = -23.6042847729804$$
$$x_{32} = -48.7152107175577$$
$$x_{32} = 61.2773745335697$$
$$x_{32} = 42.4350618814099$$
$$x_{32} = -54.9960525574964$$
$$x_{32} = -98.9702722883957$$
$$x_{32} = 23.6042847729804$$
Decrece en los intervalos
$$\left[95.8290108090195, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -95.8290108090195\right]$$