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$$- \pi^{2} \left(\frac{\pi \left(x - 1\right) \tan{\left(\frac{\pi x}{2} \right)}}{2} + 1\right) \left(\tan^{2}{\left(\frac{\pi x}{2} \right)} + 1\right) = 0$$
Resolvermos esta ecuaciónRaíces de esta ecuación
$$x_{1} = -29.9869226211336$$
$$x_{2} = -47.9917279519966$$
$$x_{3} = -55.9928891501073$$
$$x_{4} = -49.9920524148283$$
$$x_{5} = -11.9687742527727$$
$$x_{6} = -89.9955461762757$$
$$x_{7} = -77.994869591368$$
$$x_{8} = -35.9890441958502$$
$$x_{9} = 13.9687742527727$$
$$x_{10} = -41.9905733959369$$
$$x_{11} = 19.9786532361719$$
$$x_{12} = -61.993566470984$$
$$x_{13} = -53.9926305283549$$
$$x_{14} = 85.9952317659775$$
$$x_{15} = -13.9729484959255$$
$$x_{16} = 55.9926305283549$$
$$x_{17} = 89.9954460835957$$
$$x_{18} = 95.995733717172$$
$$x_{19} = -93.995733717172$$
$$x_{20} = 33.9877155958269$$
$$x_{21} = 7.94177944869404$$
$$x_{22} = -99.9959871735669$$
$$x_{23} = -97.9959061019405$$
$$x_{24} = 71.9942914583172$$
$$x_{25} = -1.86059330624841$$
$$x_{26} = 91.9955461762757$$
$$x_{27} = -57.9931302339508$$
$$x_{28} = -51.9923523825456$$
$$x_{29} = 67.9939506099815$$
$$x_{30} = -43.9909924705645$$
$$x_{31} = -71.9944478728046$$
$$x_{32} = 93.9956419634817$$
$$x_{33} = 11.9630733012144$$
$$x_{34} = 75.9945959439502$$
$$x_{35} = 39.9896062370735$$
$$x_{36} = 29.986020171625$$
$$x_{37} = 37.9890441958502$$
$$x_{38} = -83.9952317659775$$
$$x_{39} = -75.9947363220078$$
$$x_{40} = -9.96307330121439$$
$$x_{41} = -95.995821686872$$
$$x_{42} = 23.9823699155424$$
$$x_{43} = 31.9869226211336$$
$$x_{44} = -73.9945959439502$$
$$x_{45} = -31.9877155958269$$
$$x_{46} = 73.9944478728046$$
$$x_{47} = 83.9951168598645$$
$$x_{48} = 61.9933555054535$$
$$x_{49} = 3.86059330624841$$
$$x_{50} = 9.95481716686503$$
$$x_{51} = 17.9761373921869$$
$$x_{52} = 57.9928891501073$$
$$x_{53} = -33.9884178810314$$
$$x_{54} = 53.9923523825456$$
$$x_{55} = -39.9901134171449$$
$$x_{56} = 97.995821686872$$
$$x_{57} = -63.9937644514482$$
$$x_{58} = 65.9937644514483$$
$$x_{59} = -79.9949962786911$$
$$x_{60} = -27.986020171625$$
$$x_{61} = 59.9931302339508$$
$$x_{62} = -5.94177944869404$$
$$x_{63} = 5.91804806591352$$
$$x_{64} = -69.9942914583172$$
$$x_{65} = -37.9896062370735$$
$$x_{66} = 43.9905733959369$$
$$x_{67} = 35.9884178810314$$
$$x_{68} = -91.9956419634817$$
$$x_{69} = -85.9953413884714$$
$$x_{70} = -59.9933555054535$$
$$x_{71} = -21.9823699155424$$
$$x_{72} = 77.9947363220078$$
$$x_{73} = -45.9913758655731$$
$$x_{74} = -23.9837815964593$$
$$x_{75} = -7.95481716686503$$
$$x_{76} = 49.9917279519966$$
$$x_{77} = -67.994125974822$$
$$x_{78} = -19.9806888885892$$
$$x_{79} = 63.993566470984$$
$$x_{80} = 81.9949962786911$$
$$x_{81} = 41.9901134171449$$
$$x_{82} = -15.9761373921869$$
$$x_{83} = -17.9786532361719$$
$$x_{84} = 25.9837815964593$$
$$x_{85} = 45.9909924705645$$
$$x_{86} = 99.9959061019405$$
$$x_{87} = 87.9953413884714$$
$$x_{88} = 27.9849838868809$$
$$x_{89} = -81.9951168598645$$
$$x_{90} = -25.9849838868809$$
$$x_{91} = 47.9913758655731$$
$$x_{92} = 79.994869591368$$
$$x_{93} = 51.9920524148283$$
$$x_{94} = 21.9806888885892$$
$$x_{95} = -65.9939506099815$$
$$x_{96} = 69.994125974822$$
$$x_{97} = -3.91804806591352$$
$$x_{98} = 15.9729484959255$$
$$x_{99} = -87.9954460835957$$
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
$$\left[-1.86059330624841, 3.86059330624841\right]$$
Convexa en los intervalos
$$\left(-\infty, -99.9959871735669\right]$$