Can you explain how u find the x values though please
if u know the graph for sinx, u know that x =0,pi and 2pi touch the x-axis
for cosx = 1/2, u can look at the trig ratios on ur reference sheet to see which sides correspond to which angle (eg, cos = adj/hyp and on the triangle, 1/2 = 60 degrees = pi/3) or just do inverse cos times 1/2 to get the degrees, then divide by 180 to get it in radians
then u look at the unit circle and find the corresponding quadrants for sinx and cosx (which are 1st/2nd and 1st/4th respectively) and insert the angles where it fits in the domain