Answer
1
Work Step by Step
We know that if $A$ is a real number and $B\gt0$, then the graphs of $y=Asin(Bx)$ and $y=Acos(Bx)$ will have an period of $\frac{2\pi}{B}$.
Therefore, the period of the graph of $y=cos2\pi x$ is $\frac{2\pi}{2\pi}=\frac{2\pi\div2\pi}{2\pi\div2\pi}=1$.