Formal Example
A more formal proof of why system A & B from above differ is now presented. To perform this proof, the second definition will be used.
System A:
- Start with a delay of the input
- Now delay the output by
- Clearly, therefore the system is not time-invariant.
System B:
- Start with a delay of the input
- Now delay the output by
- Clearly, therefore the system is time-invariant. Although there are many other proofs, this is the easiest.
Read more about this topic: Time-invariant System
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