Hi. I have a question to ask, but I cannot find an appropriate
thread to ask. So I create this thread. Might as well, so next time
if other people have any question of the same subject, can also ask
here.
Q: How to do First Shift Theorem?
I tried to understand what is written in my lecture notes.

I tried to understand the working for one of the example
questions.

But I do not understand anything...
It would be good if someone can explain to me how to do first
shift theorem.
If you know of videos and/or online articles which explains
First Shift Theorem, please share here. Thanks.