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Homework Statement
Prove the discreet signal is periodic:
Homework Equations
for periodic funtions: x[n] = x[n + N]
The Attempt at a Solution
I made an equality (im going to leave the sigma out for simplicity):
2^(abs(n2m)) = 2^(abs(n+N2m))
I dont know what I need to do from here. The absolute value throws me off, I dont know what to do with it. My guess would be that the only thing that matters is what is inside the abs since everything else is the same so I really only need for the follwing to be true:
abs(n2m) = abs(n+N2m).......................................................(1)
but then N = 0
I guess I could make N = (2n +4m) since using this in equation (1) will get me:
abs(n2m) = abs(n+2m) = abs((n2m)) which is true. Then N can equal (2n + 4m). Now doesnt N have to be independent of n? Did I do this right? I sort of started getting the idea as I went along here so sorry if I solved it.
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