If the ROC of the system function is the exterior of a circle of radius r < ∞, including the point z = ∞, then the system is said to be:
A. Stable
B. Causal
C. Anti causal
D. None of the mentioned
Answer:A
If the ROC of the system function is the exterior of a circle of radius r < ∞, including the point z = ∞, then the system is said to be:
A. Stable B. Causal C. Anti causal D. None of the mentioned
Explanation: A linear time invariant system is said to be causal if and only if the ROC of the system function is the exterior of a circle of radius r < ∞, including the point z = ∞.