(New page: == Part B: The Basics of Linearity == === Linear System Properties === The System takes the input and creates an output following these guidelines: <math> e^{2jt} \rightarrow System \...)
 
(Linear System's response to Cos(2t))
 
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=== Linear System's response to Cos(2t) ===
 
=== Linear System's response to Cos(2t) ===
 
+
(Modified after seeing Christen Juzeszyn's answer)
  
 
Following this particular Linear System's properties:
 
Following this particular Linear System's properties:
  
<math> cos(2t) \rightarrow System \rightarrow tcos(-2t)\!</math>
+
Using Euler's formula for cos(2t):
 +
 
 +
<math> \frac{1}{2}e^{2jt} + \frac{1}{2}e^{-2jt} = \frac{1}{2}cos(2t) + \frac{1}{2}isin(2t) + \frac{1}{2}cos(2t) - \frac{1}{2}isin(2t) = cos(2t) \!</math>
 +
 
 +
<math> cos(2t) \rightarrow System \rightarrow tcos(2t)\!</math>

Latest revision as of 10:02, 16 September 2008

Part B: The Basics of Linearity

Linear System Properties

The System takes the input and creates an output following these guidelines:

$ e^{2jt} \rightarrow System \rightarrow te^{-2jt}\! $

$ e^{-2jt} \rightarrow System \rightarrow te^{2jt}\! $

Therefore the System modifies the signal accordingly:

$ x(t) \rightarrow System \rightarrow tx(-t)\! $


Linear System's response to Cos(2t)

(Modified after seeing Christen Juzeszyn's answer)

Following this particular Linear System's properties:

Using Euler's formula for cos(2t):

$ \frac{1}{2}e^{2jt} + \frac{1}{2}e^{-2jt} = \frac{1}{2}cos(2t) + \frac{1}{2}isin(2t) + \frac{1}{2}cos(2t) - \frac{1}{2}isin(2t) = cos(2t) \! $

$ cos(2t) \rightarrow System \rightarrow tcos(2t)\! $

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