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Question 4.6: Determining whether a system is time invariant Test for time......

Determining whether a system is time invariant

Test for time invariance the system whose input-output relationship is y(t) = x(t /2).

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Let x_1(t) = g(t).  Then y_1(t) = g(t/2).  Let x_2(t) = g(t − t_0 ).  Then y_2(t) = g(t /2 − t_0 ) ≠ y_1(t−t_0)= g(\frac{t − t_0}{2}). Therefore this system is not time invariant; it is time variant.

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