Graph of the function intersects the axis X at f = 0
so we need to solve the equation:
$$\frac{1}{2} - \frac{5 \sin{\left(x \right)}}{2} = 0$$
Solve this equationThe points of intersection with the axis X:
Analytical solution$$x_{1} = \pi - \operatorname{asin}{\left(\frac{1}{5} \right)}$$
$$x_{2} = \operatorname{asin}{\left(\frac{1}{5} \right)}$$
Numerical solution$$x_{1} = 31.6172844566883$$
$$x_{2} = -56.3473098438259$$
$$x_{3} = -43.7809392294668$$
$$x_{4} = 21.7897906543382$$
$$x_{5} = 90.9048290333137$$
$$x_{6} = 40.639346575877$$
$$x_{7} = -85.0243595677148$$
$$x_{8} = -41.0420624174576$$
$$x_{9} = -22.1925064959189$$
$$x_{10} = -53.6084330318168$$
$$x_{11} = 12.7677285351495$$
$$x_{12} = 6.48454322796992$$
$$x_{13} = 97.1880143404933$$
$$x_{14} = -72.4579889533556$$
$$x_{15} = 69.3163962997658$$
$$x_{16} = -1683.69230440334$$
$$x_{17} = -12.3650126935688$$
$$x_{18} = -68.9136804581851$$
$$x_{19} = 94.4491375284841$$
$$x_{20} = 46.9225318830566$$
$$x_{21} = -15.9093211887393$$
$$x_{22} = -3.34295057438012$$
$$x_{23} = 65.7720878045953$$
$$x_{24} = 72.0552731117749$$
$$x_{25} = 2.94023473279946$$
$$x_{26} = 0.201357920790331$$
$$x_{27} = -188.294201294597$$
$$x_{28} = -62.6304951510055$$
$$x_{29} = -37.4977539222872$$
$$x_{30} = 81.882766914125$$
$$x_{31} = 88.1659522213045$$
$$x_{32} = -91.3075448748943$$
$$x_{33} = 15.5066053471586$$
$$x_{34} = 19.0509138423291$$
$$x_{35} = -31.2145686151076$$
$$x_{36} = 63.0332109925862$$
$$x_{37} = -59.8916183389964$$
$$x_{38} = -24.931383307928$$
$$x_{39} = 50.466840378227$$
$$x_{40} = -78.7411742605352$$
$$x_{41} = 75.5995816069454$$
$$x_{42} = -66.174803646176$$
$$x_{43} = 9.22342003997905$$
$$x_{44} = 100.732322835664$$
$$x_{45} = 56.7500256854066$$
$$x_{46} = -28.4756918030985$$
$$x_{47} = 78.3384584189545$$
$$x_{48} = 37.9004697638678$$
$$x_{49} = -94.0464216869035$$
$$x_{50} = 84.6216437261341$$
$$x_{51} = -9.62613588155971$$
$$x_{52} = -97.5907301820739$$
$$x_{53} = 59.4889024974157$$
$$x_{54} = -100.329606994083$$
$$x_{55} = -50.0641245366464$$
$$x_{56} = -18.6481980007484$$
$$x_{57} = -34.7588771102781$$
$$x_{58} = -81.4800510725443$$
$$x_{59} = 53.2057171902362$$
$$x_{60} = -87.7632363797239$$
$$x_{61} = 34.3561612686974$$
$$x_{62} = 28.0729759615178$$
$$x_{63} = -6.08182738638926$$
$$x_{64} = 25.3340991495087$$
$$x_{65} = 44.1836550710474$$
$$x_{66} = -47.3252477246372$$
$$x_{67} = -75.1968657653647$$