Laplace transformation question

sfgoat
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Trying to answer the question:
x"+3x'+2x=u(t-1)+2(t-2)u(t-2), x(0)=1, x'(0)=-1

My book has the answer but I need to see how to solve a problem like this. Professor didn't have time to cover this section but he said one of these might be on the test. Any help is greatly appreciated.
 
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Paul's Online Math Notes has a pretty good introduction to Laplace Transforms (and so should the text used in your DE course):

http://tutorial.math.lamar.edu/Classes/DE/LaplaceIntro.aspx

There are some lecture videos here:

https://www.physicsforums.com/threads/ordinary-differential-equations.110274/

Check out Post #10 at the link above. There are 3 or 4 videos which show how to use LTs to solve ODEs for various forcing functions.

Unfortunately, PF is not set up to be a tutoring service, so after studying the material, if you have any questions, please feel free to post any follow ups.
 
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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