In general, given
[tex]y=a*tan(bx-c)+d[/tex]b is related to the period of the function, such that, in the case of the tangent function,
[tex]period=\frac{\pi}{b}[/tex]Remember that the period of tan(x) is equal to pi.
Therefore, in our case,
[tex]\begin{gathered} b=\frac{1}{2} \\ \Rightarrow period=\frac{\pi}{\frac{1}{2}}=2\pi \end{gathered}[/tex]The period of the function is 2pi, which means that it repeats every 2pi units.