El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\left(\left(\sin{\left(\frac{x}{2} \right)} + \cos{\left(\frac{x}{2} \right)}\right) + \frac{1}{5}\right)^{2} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - 4 \operatorname{atan}{\left(\frac{1}{2} \right)}$$
$$x_{2} = 4 \operatorname{atan}{\left(3 \right)}$$
Solución numérica$$x_{1} = -7.57018712716813$$
$$x_{2} = -1.8545902937402$$
$$x_{3} = 67.8280350902163$$
$$x_{4} = -52.1200727979639$$
$$x_{5} = 48.4108926372303$$
$$x_{6} = -1.85458983219618$$
$$x_{7} = -14.4209609461946$$
$$x_{8} = 23.2781503956042$$
$$x_{9} = -7.57018798349697$$
$$x_{10} = -45.2692989345745$$
$$x_{11} = -26.9873319968547$$
$$x_{12} = 60.9772623144244$$
$$x_{13} = -32.7029292386146$$
$$x_{14} = -39.5537023907713$$
$$x_{15} = 48.4108919272098$$
$$x_{16} = 92.960777033052$$
$$x_{17} = -95.5347819508756$$
$$x_{18} = 4.99618405271229$$
$$x_{19} = -20.1365587467854$$
$$x_{20} = 80.3944062897332$$
$$x_{21} = 10.7117799508857$$
$$x_{22} = 17.5625531428935$$
$$x_{23} = -77.2528143634133$$
$$x_{24} = 17.5625539431902$$
$$x_{25} = 60.9772631328613$$
$$x_{26} = -32.702928421682$$
$$x_{27} = -64.6864431369795$$
$$x_{28} = -26.9873311794228$$
$$x_{29} = 30.1289244931868$$
$$x_{30} = -39.5537010015677$$
$$x_{31} = 42.6952948902365$$
$$x_{32} = -57.8356705696945$$
$$x_{33} = 98.6763742655562$$
$$x_{34} = 67.8280362823603$$
$$x_{35} = 80.39440668751$$
$$x_{36} = -64.68644391119$$
$$x_{37} = -77.2528135593909$$
$$x_{38} = -82.9684115972995$$
$$x_{39} = 35.8445215235269$$
$$x_{40} = -95.5347822522334$$
$$x_{41} = 73.543633519085$$
$$x_{42} = -70.4020403714458$$
$$x_{43} = 55.261665889337$$
$$x_{44} = 92.9607778012846$$
$$x_{45} = 73.5436332621464$$
$$x_{46} = 48.4108930028748$$
$$x_{47} = -20.1365589281446$$
$$x_{48} = -7.57018763192014$$
$$x_{49} = -89.8191846685276$$
$$x_{50} = -57.8356701243397$$
$$x_{51} = -102.385555168247$$
$$x_{52} = 23.2781511782053$$
$$x_{53} = -20.1365580371133$$
$$x_{54} = 55.2616654308462$$
$$x_{55} = -45.2692996227957$$
$$x_{56} = 23.2781496932424$$
$$x_{57} = -57.8356698898062$$
$$x_{58} = -57.83566975998$$
$$x_{59} = -26.9873315660353$$
$$x_{60} = -1075.71169044159$$
$$x_{61} = -95.5347814178403$$
$$x_{62} = -82.9684108123697$$
$$x_{63} = 73.5436328234674$$
$$x_{64} = 80.3944071613533$$
$$x_{65} = 42.6952953662785$$
$$x_{66} = -89.8191841273032$$
$$x_{67} = 86.1100043935204$$
$$x_{68} = 35.8445210192679$$
$$x_{69} = -14.4209607980693$$
$$x_{70} = -14.4209614774142$$
$$x_{71} = 10.7117807493718$$
$$x_{72} = 4.9961827177387$$
$$x_{73} = 86.1100036738729$$
$$x_{74} = 30.1289245175727$$
$$x_{75} = -39.5537016658615$$
$$x_{76} = -1.85459057255461$$
$$x_{77} = 55.2616650739124$$
$$x_{78} = 35.8445218858112$$
$$x_{79} = -70.4020411655763$$
$$x_{80} = 42.6952946942526$$
$$x_{81} = -52.1200732680072$$
$$x_{82} = 86.1100044614437$$
$$x_{83} = 92.9607784804873$$
$$x_{84} = -45.2692993072836$$
$$x_{85} = -89.819184806985$$
$$x_{86} = 30.1289237234441$$
$$x_{87} = 4.99618349476045$$
$$x_{88} = 98.6763750575773$$
$$x_{89} = 67.8280355564391$$
$$x_{90} = -52.120072389846$$
$$x_{91} = -64.6864445156141$$