And because the spectrum of a discrete time signal, this identical spectrum will periodically repeat if we prolonged the frequency bigger beyond $f_s$ such the spectrum proven can also be the identical spectrum in every single frequency band from $nf_s$ to $(n+1)f_s$ for any integer $n$. In the firstclass he https://www.reddit.com/user/Alternative-End-2470/comments/1mbyceb/budgetfriendly_boys_pg_in_sector_14_gurgaon_for/