Diff Eq problem, Laplace Transform

DF19
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Homework Statement


Find the Laplace Transform of the given function
H(t-1)t^2

I'm not sure how to add (t-1) to the t^2 term to solve the problem

Any help would be greatly appreciated.
 
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That notation makes no sense, are you trying to translate the function on the s-axis? If you are what is the original function.
 
If the original function is e^t*t^2 the translation = F(s-1) and since f(t)=t^2 its transform is 2/s^3, therefore you substitute s-1 in for s and get 2/(s-1)^3. Unless you are doing an inverse translation on the t-axis.
 
My book states that it is a H(t) is a heavyside function and I'm suppose to use the proposition:

L{H(t-c)f(t-c)}(s)=e^(-cs)F(s)
 
Oh a unit step therefore you must translate both H(t) and F(t). LH(t-1)=e^s and f(t)=t^2, L(t^2)=2/s^3, so the transform is 2e^s/s^3
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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