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$$\left(- \frac{x^{2}}{\left(x + 4\right)^{2}} + \frac{2 x}{x + 4}\right) e^{\frac{x^{2}}{x + 4}} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = -78.9597467840785$$
$$x_{2} = -106.913335654289$$
$$x_{3} = -34.9033397297559$$
$$x_{4} = -35.1751727745241$$
$$x_{5} = -90.9333147153284$$
$$x_{6} = -86.9406036232992$$
$$x_{7} = -61.0494994577945$$
$$x_{8} = -100.919488595844$$
$$x_{9} = -88.9368046273095$$
$$x_{10} = -53.1428673334828$$
$$x_{11} = -65.0201980678831$$
$$x_{12} = -104.91524591992$$
$$x_{13} = -108.911549770027$$
$$x_{14} = -96.9243917905579$$
$$x_{15} = -112.908309811016$$
$$x_{16} = -57.088675923572$$
$$x_{17} = -92.9301010473944$$
$$x_{18} = -51.1781935426605$$
$$x_{19} = -39.6986160765956$$
$$x_{20} = -76.9658005994724$$
$$x_{21} = -116.905453690497$$
$$x_{22} = -114.906837712044$$
$$x_{23} = -82.9492865431978$$
$$x_{24} = -67.0082323315398$$
$$x_{25} = -45.3412650609875$$
$$x_{26} = -80.9542656192485$$
$$x_{27} = -41.5416914999334$$
$$x_{28} = -59.0675954479542$$
$$x_{29} = -84.9447496112777$$
$$x_{30} = -63.0338420190903$$
$$x_{31} = -102.917292451633$$
$$x_{32} = -120.902922895385$$
$$x_{33} = -72.9799763324231$$
$$x_{34} = -49.2211871942108$$
$$x_{35} = -47.2743346509508$$
$$x_{36} = -118.90415083347$$
$$x_{37} = -36.2773655522649$$
$$x_{38} = -94.9271350555347$$
$$x_{39} = -37.9251813925056$$
$$x_{40} = -8$$
$$x_{41} = -74.9725106067586$$
$$x_{42} = -55.1134523479818$$
$$x_{43} = -70.9883171472531$$
$$x_{44} = -43.4274760312326$$
$$x_{45} = -68.9976772708116$$
$$x_{46} = -110.909877655428$$
$$x_{47} = -98.9218493829935$$
$$x_{48} = -4.44230183604752$$
$$x_{49} = 0$$
Signos de extremos en los puntos:
(-78.9597467840785, 7.55684491538404e-37)
(-106.91333565428884, 5.80003112197293e-49)
(-34.90333972975594, 7.57950997191429e-18)
(-35.17517277452411, 5.80157822045189e-18)
(-90.93331471532841, 4.9096864055837e-42)
(-86.94060362329921, 2.63765684065289e-40)
(-61.04949945779446, 4.24189472183571e-29)
(-100.9194885958438, 2.30329384492659e-46)
(-88.93680462730951, 3.59955000476651e-41)
(-53.14286733348276, 1.10095574706849e-25)
(-65.02019806788307, 8.14766639443409e-31)
(-104.9152459199196, 4.26434953081264e-48)
(-108.91154977002711, 7.88683927649263e-50)
(-96.92439179055792, 1.24255445764273e-44)
(-112.90830981101571, 1.45734656186452e-51)
(-57.088675923571955, 2.18090307841584e-27)
(-92.9301010473944, 6.69352986011829e-43)
(-51.17819354266054, 7.74690995500697e-25)
(-39.69861607659563, 6.71866273571944e-20)
(-76.96580059947242, 5.5178149325211e-36)
(-116.90545369049728, 2.69081668745704e-53)
(-114.90683771204442, 1.98044565509978e-52)
(-82.9492865431978, 1.41380584334303e-38)
(-67.00823233153983, 1.12521089408103e-31)
(-45.341265060987496, 2.53092406466537e-22)
(-80.95426561924853, 1.03403344578756e-37)
(-41.541691499933364, 1.08743044477861e-20)
(-59.06759544795423, 3.04723662623038e-28)
(-84.94474961127774, 1.93170556057811e-39)
(-63.033842019090294, 5.88660712430693e-30)
(-102.91729245163262, 3.1344559727828e-47)
(-120.90292289538507, 4.96489188825533e-55)
(-72.97997633242306, 2.93282305617406e-34)
(-49.22118719421085, 5.40345511908469e-24)
(-47.27433465095077, 3.72619767124934e-23)
(-118.9041508334697, 3.65537137530554e-54)
(-36.277365552264854, 1.96101602081362e-18)
(-94.92713505553468, 9.12158846522652e-44)
(-37.92518139250562, 3.86634379096204e-19)
(-8, 1.12535174719259e-7)
(-74.9725106067586, 4.02501344387946e-35)
(-55.11345234798184, 1.55384255440091e-26)
(-70.9883171472531, 2.13430977351756e-33)
(-43.42747603123261, 1.68371480554233e-21)
(-68.99767727081155, 1.55097390960939e-32)
(-110.90987765542828, 1.07220602498669e-50)
(-98.92184938299354, 1.69201493075205e-45)
(-4.442301836047518, 4.19967870145255e-20)
(0, 1)
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:
$$x_{1} = 0$$
Puntos máximos de la función:
$$x_{1} = -8$$
Decrece en los intervalos
$$\left(-\infty, -8\right] \cup \left[0, \infty\right)$$
Crece en los intervalos
$$\left[-8, 0\right]$$