Please check if any errors in Laplace transform of my answer: f(t) = 0, 0<x<1; t-1, 1<x<2; 0 otherwise

PA3040D

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Dear experts, please advise if there are any errors or missing steps in the following Laplace transform of the waveform. Additionally, let me know if any notations are incorrect.

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Correct. But I don't understand the purpose of the last step!
I also do not have big idea, about but I followed following YouTube video which was explaining in the end of the video . Please check if you have free time

Thanks in advanced

 
This video is talking about periodic signal. Your problem in post #1 is not periodic. Therefore, dividing by [imath]1 - e^{-2s}[/imath] is wrong.

Forget the video and start over again. The first step to solve your problem is by changing the function [imath]f(t)[/imath] from a piecewise form to a new form in terms of the unit step function. Do you know how to do that?
 
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This video is talking about periodic signal. Your problem in post #1 is not periodic. Therefore, dividing by [imath]1 - e^{-2s}[/imath] is wrong.

Forget the video and start over again. The first step to solve your problem is by changing the function [imath]f(t)[/imath] from a piecewise form to a new form in terms of the unit step function. Do you know how to do that?
As far as I understand, the answer will be this. Please advise what will happen to the contents of the red-colored box during the conversion to Laplace.

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If you will write this notation:

[imath]\displaystyle f(t) = \gamma(t-1) \ u(t-1) - \gamma(t-2) \ u(t-2) - u(t-2)[/imath],

you should define [imath]\displaystyle \gamma(t) = t[/imath]

Otherwise, you should write the normal notation directly as:

[imath]\displaystyle f(t) = (t-1) \ u(t-1) - (t-2) \ u(t-2) - u(t-2)[/imath]

As far as I understand, the answer will be this. Please advise what will happen to the contents of the red-colored box during the conversion to Laplace.

View attachment 38063
[imath]\displaystyle \mathcal{L}\{\gamma(t - 1) \ u(t - 1)\} = \mathcal{L}\{\gamma(t)\} \ e^{-s}[/imath]

And

[imath]\displaystyle \mathcal{L}\{\gamma(t - 2) \ u(t - 2)\} = \mathcal{L}\{\gamma(t)\} \ e^{-2s}[/imath]
 
Dear experts, I would greatly appreciate it if someone could review my question and answer. Please let me know if my answer is correct, or if it is wrong, please point out the errors. Thank you.

Part 1) Determine the function F(t) that represent the pulse

Part 2) Determine the Laplace transform of the pulse


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Dear experts, I would greatly appreciate it if someone could review my question and answer. Please let me know if my answer is correct, or if it is wrong, please point out the errors. Thank you.

Part 1) Determine the function F(t) that represent the pulse

Part 2) Determine the Laplace transform of the pulse


View attachment 38068
This is the same problem that we have solved before!

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Your answer seems correct. Do you have any doubts of how to convert a pulse graph to another form in terms of the unit step function?
 
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