El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\frac{7}{\left(4 x + \left(- 3 x^{2} + \left(x^{4} - 2 x^{3}\right)\right)\right) + 4} \cos{\left(\left(x^{2} - x\right) - 2 \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = \frac{1}{2} - \frac{\sqrt{9 - 2 \pi}}{2}$$
$$x_{2} = \frac{1}{2} + \frac{\sqrt{9 - 2 \pi}}{2}$$
Solución numérica$$x_{1} = 66.3727459445916$$
$$x_{2} = 57.4731903164239$$
$$x_{3} = 66.6820169137914$$
$$x_{4} = 82.1333095123379$$
$$x_{5} = -21.8649823517476$$
$$x_{6} = -45.8968767416753$$
$$x_{7} = 60.9772110174711$$
$$x_{8} = 48.9504790059374$$
$$x_{9} = -67.0445907285371$$
$$x_{10} = -9.86790016807927$$
$$x_{11} = 6.16525641159366$$
$$x_{12} = 69.9027430410813$$
$$x_{13} = 63.9433557823176$$
$$x_{14} = -15.5713969917854$$
$$x_{15} = -15.374716248185$$
$$x_{16} = 8.26977889591532$$
$$x_{17} = -2.13863392314749$$
$$x_{18} = -97.9664111900668$$
$$x_{19} = 94.1757571901583$$
$$x_{20} = -100.486578104348$$
$$x_{21} = -29.1702737883955$$
$$x_{22} = -65.8242709624381$$
$$x_{23} = 10.243047946146$$
$$x_{24} = -68.6987457093266$$
$$x_{25} = -141.088071018961$$
$$x_{26} = -81.7849401297662$$
$$x_{27} = -5.94359435174751$$
$$x_{28} = -96.3742301127907$$
$$x_{29} = 22.0785754025722$$
$$x_{30} = -17.9383082266487$$
$$x_{31} = -90.0204553912285$$
$$x_{32} = 73.713634459009$$
$$x_{33} = 46.2834195273529$$
$$x_{34} = 34.0465255079919$$
$$x_{35} = -7.85429482674514$$
$$x_{36} = -40.1203809288865$$
$$x_{37} = -98.5390401214619$$
$$x_{38} = 18.2436881462729$$
$$x_{39} = 96.3964071315007$$
$$x_{40} = 100.250203696995$$
$$x_{41} = -51.8764220833869$$
$$x_{42} = 29.528021545315$$
$$x_{43} = 30.1702737883955$$
$$x_{44} = 39.1791585583496$$
$$x_{45} = -65.4918678440659$$
$$x_{46} = 94.1422143044595$$
$$x_{47} = 11.740236199333$$
$$x_{48} = -53.7908197832786$$
$$x_{49} = -3.9191356162426$$
$$x_{50} = -8.22223752023299$$
$$x_{51} = -67.5542928481706$$
$$x_{52} = 72.0425302625716$$
$$x_{53} = -66.5778643340245$$
$$x_{54} = 4.13944697551211$$
$$x_{55} = 41.8865582028712$$
$$x_{56} = -41.7504891203902$$
$$x_{57} = 74.0988107136386$$
$$x_{58} = -23.3601650030539$$
$$x_{59} = -70.9986045392761$$
$$x_{60} = 20.2544094500023$$
$$x_{61} = 25.0096593307385$$
$$x_{62} = -71.1960583640838$$
$$x_{63} = 20.5699542434132$$
$$x_{64} = 78.2502634669489$$
$$x_{65} = -56.6108779314362$$
$$x_{66} = 51.3238956094868$$
$$x_{67} = 58.0492646395838$$
$$x_{68} = 44.176377418488$$
$$x_{69} = 61.3139273271213$$
$$x_{70} = 105.13808867441$$
$$x_{71} = 48.9180474952387$$
$$x_{72} = 36.0029274534187$$
$$x_{73} = -53.76187906889$$
$$x_{74} = -2518.79302359967$$
$$x_{75} = -77.8540123336875$$
$$x_{76} = -23.6870923684701$$
$$x_{77} = -35.7905845299759$$
$$x_{78} = 14.2540816810354$$
$$x_{79} = 57.1136353746586$$
$$x_{80} = 82.6129529263009$$
$$x_{81} = -53.0039261278414$$
$$x_{82} = -151.56183325902$$
$$x_{83} = -98.9031594025718$$
$$x_{84} = -93.7774884088388$$
$$x_{85} = -43.7835524716936$$
$$x_{86} = 90.7597859205944$$