based on function transformations, the graph of y= cos(2θ), is the same as the graph of y= cos(θ), with a component B of 2, in which case, it means the period is the only thing that differs
well the period for this function will then be [tex]\bf \cfrac{2\pi }{B}\iff \cfrac{2\pi }{2}\implies \pi [/tex]
so, the graph of is, the same as y= cos(θ), just shrunk by half horizontally
