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  1. MHB Apprentice

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    #1


    Problem: Find a (limited?) solution to the diff eq.





    At the end of the solution, when you transform $ \displaystyle \frac{-1}{s+1} + \frac{2}{s-3}$
    why doesnt it become $ \displaystyle -e^{-t} + 2e^{3t} $, t>0 ?

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  3. MHB Master
    MHB Math Helper

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    #2
    That would be correct if the right hand side of the equation were 0. But the delta functions on the right mean that those are correct only for x greater than certain values so the step functions are needed.

  4. MHB Apprentice

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    #3 Thread Author
    What values are those and how are the step functions used?

  5. MHB Master
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    #4
    Do you know what "$ \displaystyle \delta(x)$" and "$ \displaystyle \delta'(x)$" mean?

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