Hallemos los puntos de flexiones, para eso hay que resolver la ecuación
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = 0$$
(la segunda derivada es igual a cero),
las raíces de la ecuación obtenida serán los puntos de flexión para el gráfico de la función indicado:
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = $$
segunda derivada$$6 \left(\tan^{2}{\left(x^{2} + e \right)} + 1\right) \left(4 x^{2} \left(\tan^{2}{\left(x^{2} + e \right)} + 1\right) + 4 x^{2} \tan^{2}{\left(x^{2} + e \right)} + \tan{\left(x^{2} + e \right)}\right) \tan{\left(x^{2} + e \right)} = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = -75.7427983129756$$
$$x_{2} = -34.0077845109936$$
$$x_{3} = -84.0026214518797$$
$$x_{4} = -74.086339338953$$
$$x_{5} = -29.981974747368$$
$$x_{6} = 24.2466727005258$$
$$x_{7} = -39.7573190190284$$
$$x_{8} = -15.7673437984565$$
$$x_{9} = 89.996939791193$$
$$x_{10} = 94.3094486949099$$
$$x_{11} = 42.2474607291862$$
$$x_{12} = 30.2427970435897$$
$$x_{13} = 52.2538737970178$$
$$x_{14} = 49.8225000091431$$
$$x_{15} = -19.7479315339674$$
$$x_{16} = 0.268698338105772$$
$$x_{17} = -93.9924563607082$$
$$x_{18} = -61.7601553777445$$
$$x_{19} = 19.9851339207681$$
$$x_{20} = -27.750919101079$$
$$x_{21} = 46.2584901171642$$
$$x_{22} = -53.9983452835034$$
$$x_{23} = -43.8887184533301$$
$$x_{24} = 98.0013880149109$$
$$x_{25} = 92.0163871940733$$
$$x_{26} = 66.2512509156625$$
$$x_{27} = 60.0057371577005$$
$$x_{28} = -79.9990471579977$$
$$x_{29} = 70.2557141420874$$
$$x_{30} = 100.173201238609$$
$$x_{31} = -35.7638297842412$$
$$x_{32} = 4.01637574102321$$
$$x_{33} = -4.01637574102321$$
$$x_{34} = 32.3021991792655$$
$$x_{35} = 82.2451961758494$$
$$x_{36} = 78.2520759639745$$
$$x_{37} = 56.2495076688681$$
$$x_{38} = 64.2532182668084$$
$$x_{39} = 6.17433580785887$$
$$x_{40} = 7.95331150508558$$
$$x_{41} = -56.0536882320416$$
$$x_{42} = 48.2529114886881$$
$$x_{43} = -23.9861369635059$$
$$x_{44} = -99.79615234419$$
$$x_{45} = -18.000204280643$$
$$x_{46} = 34.2379521965629$$
$$x_{47} = 36.2437448399812$$
$$x_{48} = -77.7486178419391$$
$$x_{49} = -58.0092151543166$$
$$x_{50} = -65.7514623576137$$
$$x_{51} = -7.75329421880383$$
$$x_{52} = 80.0186799368818$$
$$x_{53} = 62.2415219343273$$
$$x_{54} = -25.7545988268615$$
$$x_{55} = -22.0051943749188$$
$$x_{56} = 53.9983452835034$$
$$x_{57} = -31.7627856559757$$
$$x_{58} = -69.9869006155553$$
$$x_{59} = 16.2578317658498$$
$$x_{60} = 74.2557635330431$$
$$x_{61} = -95.7475361249581$$
$$x_{62} = -51.7403155352152$$
$$x_{63} = 76.0119214385267$$
$$x_{64} = -47.9917776906258$$
$$x_{65} = -45.746300594867$$
$$x_{66} = 10.2027382791873$$
$$x_{67} = 39.9936741435735$$
$$x_{68} = -9.72990701049216$$
$$x_{69} = 1.88809519853225$$
$$x_{70} = 13.9714729126065$$
$$x_{71} = 18.000204280643$$
$$x_{72} = 68.0062327798659$$
$$x_{73} = 43.8529134131597$$
$$x_{74} = 22.0051943749188$$
$$x_{75} = -72.0003554800134$$
$$x_{76} = 28.2557577289468$$
$$x_{77} = -89.752252755178$$
$$x_{78} = -67.7516802575391$$
$$x_{79} = -85.9984442729955$$
$$x_{80} = -41.7613126418156$$
$$x_{81} = 58.2524109089238$$
$$x_{82} = 72.0003554800134$$
$$x_{83} = -64.0082817384299$$
$$x_{84} = 38.2675513640209$$
$$x_{85} = -13.7447761000505$$
$$x_{86} = -98.0013880149109$$
$$x_{87} = -81.381205598052$$
$$x_{88} = -11.7751173065529$$
$$x_{89} = -87.7523042704504$$
$$x_{90} = 12.2971443106699$$
$$x_{91} = 96.254766356069$$
$$x_{92} = -5.64262681390757$$
$$x_{93} = 25.9974177822902$$
$$x_{94} = -91.9993147778614$$
$$x_{95} = 88.7313614271817$$
$$x_{96} = -49.727826507905$$
$$x_{97} = 84.2453625743546$$
$$x_{98} = -59.7433893021072$$
$$x_{99} = -1.88809519853225$$
$$x_{100} = 86.2537808709031$$
Intervalos de convexidad y concavidad:Hallemos los intervales donde la función es convexa o cóncava, para eso veamos cómo se comporta la función en los puntos de flexiones:
Cóncava en los intervalos
$$\left[100.173201238609, \infty\right)$$
Convexa en los intervalos
$$\left[0.268698338105772, 1.88809519853225\right]$$