And Because the spectrum of a discrete time sign, this exact spectrum will periodically repeat if we extended the frequency higher over and above $f_s$ such the spectrum proven is also a similar spectrum in just about every frequency band from $nf_s$ to $(n+one)f_s$ for just about any integer $n$. https://pgforboysingurugram.blogspot.com/2025/07/affordable-boys-pg-in-gurgaon-sector-15.html