El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\frac{x + 1}{\left(x x + 1\right)^{2}} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = -1$$
Solución numérica$$x_{1} = -34832.4270840261$$
$$x_{2} = 28749.5424513273$$
$$x_{3} = 35529.1830671647$$
$$x_{4} = -17885.5101822959$$
$$x_{5} = 37224.160496723$$
$$x_{6} = 21970.6266224823$$
$$x_{7} = 33834.2285454912$$
$$x_{8} = 9267.45404568973$$
$$x_{9} = -15344.4829215851$$
$$x_{10} = -9419.33329706892$$
$$x_{11} = 20276.0946617741$$
$$x_{12} = -33984.9574174783$$
$$x_{13} = -23816.0806573264$$
$$x_{14} = 21123.3472938935$$
$$x_{15} = 10959.7950148984$$
$$x_{16} = -29747.7255943491$$
$$x_{17} = 36376.6691166606$$
$$x_{18} = -12804.1871325825$$
$$x_{19} = -26358.1255649569$$
$$x_{20} = 24512.5974895349$$
$$x_{21} = -37374.873078274$$
$$x_{22} = -19579.7911539546$$
$$x_{23} = 11806.2655234967$$
$$x_{24} = 32986.7609668844$$
$$x_{25} = -22968.7707704751$$
$$x_{26} = 40614.1727065763$$
$$x_{27} = -30595.1542455215$$
$$x_{28} = 27054.7245350401$$
$$x_{29} = -11957.667829554$$
$$x_{30} = 16887.4298531687$$
$$x_{31} = -33137.4947143549$$
$$x_{32} = -14497.6168493628$$
$$x_{33} = -22121.4838361446$$
$$x_{34} = -41612.3835710987$$
$$x_{35} = 15193.3840611629$$
$$x_{36} = -17038.4405090108$$
$$x_{37} = -21274.2226481452$$
$$x_{38} = -42459.8980123181$$
$$x_{39} = -20426.9904729273$$
$$x_{40} = -40764.8728987272$$
$$x_{41} = 41461.6860120789$$
$$x_{42} = -18732.6292450164$$
$$x_{43} = -39069.8638512438$$
$$x_{44} = -39917.3662375731$$
$$x_{45} = 31291.8477670117$$
$$x_{46} = 17734.5344763108$$
$$x_{47} = 39766.6632424023$$
$$x_{48} = 16040.3768972116$$
$$x_{49} = -35679.9032124213$$
$$x_{50} = 13499.622908825$$
$$x_{51} = -16191.4281723745$$
$$x_{52} = -32290.0395295242$$
$$x_{53} = 30444.4033541377$$
$$x_{54} = 22817.9297180831$$
$$x_{55} = 29596.9679855437$$
$$x_{56} = 42309.2029299978$$
$$x_{57} = 19428.8721576817$$
$$x_{58} = 14346.4617481587$$
$$x_{59} = -10265.1883488199$$
$$x_{60} = -24663.4110930219$$
$$x_{61} = 38919.1578682278$$
$$x_{62} = -31442.592478417$$
$$x_{63} = 32139.3005164984$$
$$x_{64} = 18581.6838276728$$
$$x_{65} = 10113.508304835$$
$$x_{66} = -27205.5062138373$$
$$x_{67} = 38071.6568546614$$
$$x_{68} = -38222.3660269625$$
$$x_{69} = 25359.9581060261$$
$$x_{70} = 27902.1276363793$$
$$x_{71} = -28052.9005589566$$
$$x_{72} = 26207.3342685621$$
$$x_{73} = 34681.7027350514$$
$$x_{74} = -36527.3853481304$$
$$x_{75} = -11111.3201545584$$
$$x_{76} = -13650.8451413168$$
$$x_{77} = 23665.2540647425$$
$$x_{78} = -28900.3073791784$$
$$x_{79} = 12652.8838720334$$
$$x_{80} = -25510.7599982124$$