# Easy Laplace Transform help!

#### winbacker

"easy" Laplace Transform...help!

1. The problem statement, all variables and given/known data

Evaluate L{(e^-2t)*t*sinht}

2. Relevant equations

translation theorem

3. The attempt at a solution

Just to clarify: the contents of the bracket is the product of 3 terms:
e^-2t (e to the power of -2t)
t
sinht

all multiplied together.

I am ok with finding the laplace of 2 term products but with 3 terms I do not know where to begin. All I can think of is that the presence of the euler term suggests the use of the 2nd translation theorem.

Any help would be appreciated.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

Related Calculus and Beyond Homework News on Phys.org

#### rock.freak667

Homework Helper
Re: "easy" Laplace Transform...help!

Now use the fact that L(tf(t)}= -F'(s)

Now just apply the shift property for L{e-2tf(t)}

#### phsopher

Re: "easy" Laplace Transform...help!

You can express sinh t in terms of e^t and e^-t. Do that and combine all the exponentials together. That way you can express the whole thing as a sum of Laplace transforms of t at different points.

"Easy Laplace Transform help!"

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