Express y(t) as a function of x(t)

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The discussion focuses on expressing y(t) as a function of x(t) through various transformations, leading to the equation y(t) = -0.5x(2t-4)+1.5. A plot is provided to compare the derived function with a figure from a textbook, revealing discrepancies in the time interval 4 < t < 5. Participants note that the time scale in the book is compressed, which complicates the comparison. There is uncertainty about whether the book's figure should match the derived plot, indicating potential issues with the textbook representation. The conversation highlights the challenges in accurately representing functions and transformations in time-based systems.
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Homework Statement


Express y(t) as a function of x(t).

https://www.physicsforums.com/attachment.php?attachmentid=61309&d=1378005939

Homework Equations




The Attempt at a Solution


Transformations:
-x(t)
0.5x(t)
x(2t)
x(t-2)
x(t)+1.5

∴y(t) = -0.5x(2t-4)+1.5

Here is the plot:

attachment.png


As seen in the plot above, it is different from the figure in the book (P2.4(b)) on the time interval 4 < t < 5. Where am I going wrong?

Thanks!
 

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It seems that your answer is correct.
 
I just noticed that the time scale for 4 < t < 5 remains the same for the figure in the book. I know the time scale is compressed by 0.5 up until t = 4. So, is the book's figure supposed to look like my plot instead? It seems impossible to express y(t) as a function of x(t) if I use the figure in the book.
 
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