Remember that cosine is positive in the first and fourth quadrants.
To get the angle that's in the first quadrant, we solve for Theta as following:
[tex]\begin{gathered} \cos \theta=\frac{\sqrt[]{3}}{2} \\ \\ \rightarrow\theta=\cos ^{-1}(\frac{\sqrt[]{3}}{2}) \\ \\ \Rightarrow\theta=30 \end{gathered}[/tex]To get the angle in teh fourth quadrant, we substract the calculated angle from 360°
[tex]360-30=330[/tex]Therefore, the two angles we're looking for are 30° and 330°