El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\sin{\left(9 x \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = 0$$
$$x_{2} = \frac{\pi}{9}$$
Solución numérica$$x_{1} = 84.1248699461267$$
$$x_{2} = -91.8043186549017$$
$$x_{3} = -45.7276264022514$$
$$x_{4} = 8.02851455917392$$
$$x_{5} = 42.2369678982628$$
$$x_{6} = -49.9164166070378$$
$$x_{7} = -83.7758040957278$$
$$x_{8} = -69.8131700797732$$
$$x_{9} = -17.8023583703422$$
$$x_{10} = 46.0766922526503$$
$$x_{11} = 43.9822971502571$$
$$x_{12} = 76.0963553869528$$
$$x_{13} = -75.7472895365539$$
$$x_{14} = -57.9449311662117$$
$$x_{15} = 100.181899064475$$
$$x_{16} = -11.8682389135614$$
$$x_{17} = 18.151424220741$$
$$x_{18} = -21.9911485751286$$
$$x_{19} = -13.9626340159546$$
$$x_{20} = 78.190750489346$$
$$x_{21} = 0$$
$$x_{22} = -52.010811709431$$
$$x_{23} = 4.18879020478639$$
$$x_{24} = -85.870199198121$$
$$x_{25} = -55.8505360638185$$
$$x_{26} = 38.0481776934764$$
$$x_{27} = -30.0196631343025$$
$$x_{28} = -33.85938748869$$
$$x_{29} = -90.0589894029074$$
$$x_{30} = 70.162235930172$$
$$x_{31} = 95.9931088596881$$
$$x_{32} = -3.83972435438753$$
$$x_{33} = 74.0019602845596$$
$$x_{34} = -1.74532925199433$$
$$x_{35} = 10.1229096615671$$
$$x_{36} = -31.7649923862968$$
$$x_{37} = 60.0393262686049$$
$$x_{38} = 86.2192650485199$$
$$x_{39} = 62.1337213709981$$
$$x_{40} = -59.6902604182061$$
$$x_{41} = 86.9173967493176$$
$$x_{42} = 32.1140582366957$$
$$x_{43} = -35.9537825910832$$
$$x_{44} = 30.0196631343025$$
$$x_{45} = -74.0019602845596$$
$$x_{46} = 34.2084533390889$$
$$x_{47} = -15.0098315671512$$
$$x_{48} = -5.93411945678072$$
$$x_{49} = -82.0304748437335$$
$$x_{50} = -23.7364778271229$$
$$x_{51} = -97.7384381116825$$
$$x_{52} = -47.8220215046446$$
$$x_{53} = -25.8308729295161$$
$$x_{54} = -53.7561409614254$$
$$x_{55} = 21.9911485751286$$
$$x_{56} = 56.1996019142174$$
$$x_{57} = 54.1052068118242$$
$$x_{58} = 48.1710873550435$$
$$x_{59} = 12.2173047639603$$
$$x_{60} = -9.77384381116824$$
$$x_{61} = -27.9252680319093$$
$$x_{62} = -8.02851455917392$$
$$x_{63} = 68.0678408277789$$
$$x_{64} = 52.010811709431$$
$$x_{65} = 13.2645023151569$$
$$x_{66} = 50.2654824574367$$
$$x_{67} = 80.634211442138$$
$$x_{68} = -87.9645943005142$$
$$x_{69} = 24.0855436775217$$
$$x_{70} = 20.2458193231342$$
$$x_{71} = -99.8328332140756$$
$$x_{72} = -79.9360797413403$$
$$x_{73} = 28.2743338823081$$
$$x_{74} = 16.0570291183478$$
$$x_{75} = 82.0304748437335$$
$$x_{76} = -61.7846555205993$$
$$x_{77} = -65.9734457253857$$
$$x_{78} = 92.1533845053006$$
$$x_{79} = 72.2566310325652$$
$$x_{80} = -41.8879020478639$$
$$x_{81} = -77.8416846389471$$
$$x_{82} = 6.28318530717959$$
$$x_{83} = -67.71877497738$$
$$x_{84} = -93.8987137572949$$
$$x_{85} = 94.2477796076938$$
$$x_{86} = 65.9734457253857$$
$$x_{87} = -43.9822971502571$$
$$x_{88} = 40.1425727958696$$
$$x_{89} = 64.2281164733913$$
$$x_{90} = -19.8967534727354$$
$$x_{91} = -71.9075651821664$$
$$x_{92} = -39.7935069454707$$
$$x_{93} = 26.1799387799149$$
$$x_{94} = -63.8790506229925$$
$$x_{95} = 2.0943951023932$$
$$x_{96} = -95.9931088596881$$
$$x_{97} = 90.0589894029074$$
$$x_{98} = 98.0875039620813$$