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Laplace transform of anti causal systems

  1. May 29, 2015 #1
    The unilateral laplace transform integrates from 0 to infinity.Then how can i take laplace transform of exp(t)u(-t)?PS:I don't want to flip it and use time scaling property.
  2. jcsd
  3. May 29, 2015 #2


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    What is the function u(-t) in your question?

    The Laplace transform applies to functions. The variable is not a time variable, but simply an integration variable. It does not know what is the nature of those functions. If the integral is defined, finite, and well formed, then that's the transform. If it is not well formed or diverges or is not defined, then the same applies to the transform.

    Depending on your application the Laplace transform may work just fine, may not be helpful, or may not be appropriate at all. It is very hard to tell from the small hints you have given.
  4. May 31, 2015 #3
    It is the flipped unit step function...u(-t)=1 -inf<t<=0
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