Graph of the function intersects the axis X at f = 0
so we need to solve the equation:
$$6 \sqrt{\sin{\left(x \right)}} - 1 = 0$$
Solve this equationThe points of intersection with the axis X:
Analytical solution$$x_{1} = \pi - \operatorname{asin}{\left(\frac{1}{36} \right)}$$
$$x_{2} = \operatorname{asin}{\left(\frac{1}{36} \right)}$$
Numerical solution$$x_{1} = 97.3615909100198$$
$$x_{2} = -15.7357446192128$$
$$x_{3} = -122.549894841266$$
$$x_{4} = -43.9545157989933$$
$$x_{5} = 15.6801819166852$$
$$x_{6} = -40.8684858479311$$
$$x_{7} = -18.821774570275$$
$$x_{8} = 44.0100785015209$$
$$x_{9} = 78.512034988481$$
$$x_{10} = 84.7952202956606$$
$$x_{11} = -56.5208864133525$$
$$x_{12} = -53.4348564622903$$
$$x_{13} = -75.3704423348912$$
$$x_{14} = -100.50318356361$$
$$x_{15} = 9.39699660950558$$
$$x_{16} = -78.5675976910086$$
$$x_{17} = -12.5385892630954$$
$$x_{18} = 40.8129231454035$$
$$x_{19} = 12.594151965623$$
$$x_{20} = -50.2377011061729$$
$$x_{21} = -66.0012270766495$$
$$x_{22} = -87.9368129492504$$
$$x_{23} = 94.2755609589576$$
$$x_{24} = 91.0784056028402$$
$$x_{25} = 37.7268931943413$$
$$x_{26} = -6.25540395591579$$
$$x_{27} = -9.45255931203318$$
$$x_{28} = -34.5853005407515$$
$$x_{29} = 34.5297378382239$$
$$x_{30} = -72.284412383829$$
$$x_{31} = -91.1339683053678$$
$$x_{32} = -47.1516711551107$$
$$x_{33} = 21.9633672238648$$
$$x_{34} = -3.16937400485359$$
$$x_{35} = 72.2288496813015$$
$$x_{36} = -84.8507829981882$$
$$x_{37} = 87.992375651778$$
$$x_{38} = -94.21999825643$$
$$x_{39} = 47.0961084525831$$
$$x_{40} = 69.1428197302393$$
$$x_{41} = 25.1605225799821$$
$$x_{42} = 59.6624790669423$$
$$x_{43} = -22.0189299263923$$
$$x_{44} = -37.6713304918137$$
$$x_{45} = 6.31096665844338$$
$$x_{46} = -116.266709534086$$
$$x_{47} = 3.113811302326$$
$$x_{48} = -62.8040717205321$$
$$x_{49} = -31.3881451846341$$
$$x_{50} = -97.4171536125474$$
$$x_{51} = -69.0872570277117$$
$$x_{52} = 75.4260050374188$$
$$x_{53} = 50.2932638087005$$
$$x_{54} = 0.0277813512637952$$
$$x_{55} = 53.3792937597627$$
$$x_{56} = 62.8596344230597$$
$$x_{57} = 81.7091903445984$$
$$x_{58} = -25.1049598774546$$
$$x_{59} = -28.3021152335719$$
$$x_{60} = 56.5764491158801$$
$$x_{61} = -50.2377011061729$$
$$x_{62} = 28.2465525310443$$
$$x_{63} = -59.7180417694699$$
$$x_{64} = 31.4437078871617$$
$$x_{65} = 18.8773372728026$$
$$x_{66} = 65.9456643741219$$
$$x_{67} = 100.558746266137$$
$$x_{68} = -81.6536276420708$$