El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\frac{x}{\left(x^{2} + 9\right)^{2}} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = 0$$
Solución numérica$$x_{1} = 12875.9356644959$$
$$x_{2} = -10227.3059058482$$
$$x_{3} = 11195.4249182631$$
$$x_{4} = -32181.633895865$$
$$x_{5} = 30619.6171640105$$
$$x_{6} = 35699.5044289087$$
$$x_{7} = 34852.7401733255$$
$$x_{8} = 36546.3076737797$$
$$x_{9} = -26257.0693139798$$
$$x_{10} = -11905.0651910039$$
$$x_{11} = -36415.1956001117$$
$$x_{12} = 23850.2473093557$$
$$x_{13} = 10356.9901524436$$
$$x_{14} = -37262.0297461262$$
$$x_{15} = -15272.2465667959$$
$$x_{16} = 32312.7120492531$$
$$x_{17} = 13717.5598160212$$
$$x_{18} = 29773.1600728685$$
$$x_{19} = -9390.81474028311$$
$$x_{20} = -12745.6949815305$$
$$x_{21} = -28795.7307048517$$
$$x_{22} = 23004.5521230026$$
$$x_{23} = 19623.424641841$$
$$x_{24} = 20468.4173629607$$
$$x_{25} = -13587.1991804469$$
$$x_{26} = -11065.512174912$$
$$x_{27} = 39933.8608686795$$
$$x_{28} = 17934.1819273169$$
$$x_{29} = 31466.1361133273$$
$$x_{30} = -22028.1009649222$$
$$x_{31} = -38955.7986308119$$
$$x_{32} = 28926.7702829501$$
$$x_{33} = 16246.1887015522$$
$$x_{34} = -17803.4556987779$$
$$x_{35} = -27949.4262152958$$
$$x_{36} = 39086.9259665187$$
$$x_{37} = 27234.217770454$$
$$x_{38} = -35568.3981832179$$
$$x_{39} = -22873.6257966223$$
$$x_{40} = 0$$
$$x_{41} = 28080.4538951085$$
$$x_{42} = -33028.2546059133$$
$$x_{43} = -29642.1096011699$$
$$x_{44} = -23719.299478082$$
$$x_{45} = 21313.6182094681$$
$$x_{46} = -27103.2031210464$$
$$x_{47} = 17090.0058231518$$
$$x_{48} = -31335.066443146$$
$$x_{49} = 15402.7900395067$$
$$x_{50} = -34721.6401870687$$
$$x_{51} = -40649.6876492696$$
$$x_{52} = 24696.0737334108$$
$$x_{53} = 41627.812487716$$
$$x_{54} = 42474.8259378535$$
$$x_{55} = -38108.89816921$$
$$x_{56} = -25411.0337401088$$
$$x_{57} = 22159.0032599515$$
$$x_{58} = -18647.8970830298$$
$$x_{59} = -16959.3314832694$$
$$x_{60} = 12035.1593886819$$
$$x_{61} = -41496.6726056829$$
$$x_{62} = -14429.4231205362$$
$$x_{63} = -42343.6823669146$$
$$x_{64} = -16115.5746430474$$
$$x_{65} = -39802.7290831404$$
$$x_{66} = 18778.6682957106$$
$$x_{67} = 34006.0178245556$$
$$x_{68} = 38240.0207552378$$
$$x_{69} = -33874.924572849$$
$$x_{70} = 26388.0696525683$$
$$x_{71} = -30488.5566933999$$
$$x_{72} = -24565.1065816366$$
$$x_{73} = 37393.1472550726$$
$$x_{74} = 25542.0183140732$$
$$x_{75} = 14559.8832146339$$
$$x_{76} = 33159.3405986285$$
$$x_{77} = -21182.7428839706$$
$$x_{78} = 40780.8236095103$$
$$x_{79} = -20337.5724442947$$
$$x_{80} = 9520.20568161211$$
$$x_{81} = -19492.614177059$$