El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$- \sin{\left(2 x \right)} - \cos{\left(2 x \right)} = 0$$
Resolvermos esta ecuaciónPuntos de cruce con el eje X:
Solución analítica$$x_{1} = - \frac{\pi}{8}$$
Solución numérica$$x_{1} = -99.3528676697772$$
$$x_{2} = -91.4988860358027$$
$$x_{3} = -25.5254403104171$$
$$x_{4} = 70.2931356240716$$
$$x_{5} = 84.4303025652257$$
$$x_{6} = 65.5807466436869$$
$$x_{7} = 86.0010988920206$$
$$x_{8} = -11.388273369263$$
$$x_{9} = -3.53429173528852$$
$$x_{10} = -39.6626072515711$$
$$x_{11} = 20.0276531666349$$
$$x_{12} = 27.8816348006094$$
$$x_{13} = -77.3617190946487$$
$$x_{14} = 9.03207887907065$$
$$x_{15} = -61.6537558266997$$
$$x_{16} = -9.8174770424681$$
$$x_{17} = -69.5077374606742$$
$$x_{18} = -97.7820713429823$$
$$x_{19} = -67.9369411338793$$
$$x_{20} = 18.45685683984$$
$$x_{21} = 76.5763209312512$$
$$x_{22} = -80.5033117482384$$
$$x_{23} = 49.872783375738$$
$$x_{24} = -55.3705705195201$$
$$x_{25} = 2.74889357189107$$
$$x_{26} = 4.31968989868597$$
$$x_{27} = 64.009950316892$$
$$x_{28} = -30.2378292908018$$
$$x_{29} = -75.7909227678538$$
$$x_{30} = 48.3019870489431$$
$$x_{31} = 56.1559686829176$$
$$x_{32} = -52.2289778659303$$
$$x_{33} = 71.8639319508665$$
$$x_{34} = 98.5674695063798$$
$$x_{35} = -45.9457925587507$$
$$x_{36} = 24.7400421470196$$
$$x_{37} = 26.3108384738145$$
$$x_{38} = -36.5210145979813$$
$$x_{39} = -38.0918109247762$$
$$x_{40} = -16.1006623496477$$
$$x_{41} = 32.5940237809941$$
$$x_{42} = 18993.6764845222$$
$$x_{43} = -31.8086256175967$$
$$x_{44} = -44.3749962319558$$
$$x_{45} = -47.5165888855456$$
$$x_{46} = 46.7311907221482$$
$$x_{47} = -17.6714586764426$$
$$x_{48} = -66.3661448070844$$
$$x_{49} = -74.2201264410589$$
$$x_{50} = 12.1736715326604$$
$$x_{51} = -23.9546439836222$$
$$x_{52} = -33.3794219443916$$
$$x_{53} = 40.4480054149686$$
$$x_{54} = -89.9280897090078$$
$$x_{55} = 13.7444678594553$$
$$x_{56} = -60.0829594999048$$
$$x_{57} = -8.24668071567321$$
$$x_{58} = -1.96349540849362$$
$$x_{59} = -88.3572933822129$$
$$x_{60} = -96.2112750161874$$
$$x_{61} = -82.0741080750334$$
$$x_{62} = 54.5851723561227$$
$$x_{63} = -83.6449044018282$$
$$x_{64} = -22.3838476568273$$
$$x_{65} = 90.7134878724053$$
$$x_{66} = 79.717913584841$$
$$x_{67} = 93.8550805259951$$
$$x_{68} = -53.7997741927252$$
$$x_{69} = 10.6028752058656$$
$$x_{70} = 34.164820107789$$
$$x_{71} = 68.7223392972767$$
$$x_{72} = 5.89048622548086$$
$$x_{73} = 57.7267650097125$$
$$x_{74} = -41.233403578366$$
$$x_{75} = 43.5895980685584$$
$$x_{76} = -19.2422550032375$$
$$x_{77} = 87.5718952188155$$
$$x_{78} = 21.5984494934298$$
$$x_{79} = -0.392699081698724$$
$$x_{80} = -58.5121631731099$$
$$x_{81} = -184.175869316702$$
$$x_{82} = 78.1471172580461$$
$$x_{83} = 100.138265833175$$
$$x_{84} = 62.4391539900971$$
$$x_{85} = 35.7356164345839$$
$$x_{86} = 92.2842841992002$$
$$x_{87} = 42.0188017417635$$