Use the Shifting Theorem to find the Laplace transform

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    Laplace Transform
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Homework Statement
Please see below
Relevant Equations
Shifting theorem
For (b),
1713665142390.png

I'm confused on the highlighted step. Does someone please explain to me how they got from the left to the right?

Thanks!
 
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cos(a-b)=cos(a)cos(b)+sin(a)sin(b) and cos(π/4)=sin(π/4)=1/√2
 
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Note again the typos in the solution. For example the ##1/\sqrt 2## multiplying only one of the terms. The amount of typos in your problems is really beyond critisism. It is outright embarrassing to whatever institution is giving these out.
 
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Orodruin said:
Note again the typos in the solution. For example the ##1/\sqrt 2## multiplying only one of the terms. The amount of typos in your problems is really beyond critisism. It is outright embarrassing to whatever institution is giving these out.
Criticism.
 
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WWGD said:
Criticism.
Valid critisism. I have no idea where OP is studying, but I know that in every single problem they have posted the provided solution has been full of typos. Many times those typos have been the source of OP’s confusion.
 
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