Final answer:
To determine if a discrete-time signal is periodic, we can check if there is a fundamental period by finding the smallest positive integer 'N' for which the signal repeats.
Step-by-step explanation:
A discrete-time signal is periodic if it repeats itself after a certain interval. To determine if a signal is periodic, we need to check if there is a fundamental period, which is the smallest possible interval after which the signal repeats. If the signal is periodic, we can determine its fundamental period by finding the smallest positive integer 'N' for which the signal satisfies the condition:
x[n] = x[n+N]
where 'x[n]' is the discrete-time signal. If there is no such 'N' that satisfies the condition, then the signal is not periodic.