(Part A)
(Part B)
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the system is time variant (by not fitting the definition of time invariance).
 
the system is time variant (by not fitting the definition of time invariance).
  
== Part B ==
+
== Part B: Find input given output ==
 
LAWL
 
LAWL

Revision as of 20:30, 11 September 2008

Part A: Can the system be time invariant?

The system cannot be time invariant.


For instance, the input

$ \,X_0[n]=\delta [n]\, $

yields the output

$ \,Y_0[n]=\delta [n-1]\, $

Thus,

$ \,Y_0[n-1]=\delta [n-2]\, $


However, the input

$ \,X_0[n-1]=\delta [n-1]=X_1[n]\, $

yields the output

$ \,Y_1[n]=4\delta[n-2]\, $


Since these two are not equal

$ \,\delta [n-2]\not= 4\delta[n-2]\, $

the system is time variant (by not fitting the definition of time invariance).

Part B: Find input given output

LAWL

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Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett