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Homework Help: Limit of an exponent when it goes to infinity

  1. Mar 25, 2010 #1
    how this thing works ?

    integration of e to the power of (-x) from 0 to infinity

    sorry , not good in using the symbols ..^.^ ~
     
  2. jcsd
  3. Mar 25, 2010 #2
    Hi
    Do you know what the primitive of e^{-x} is ?
     
  4. Mar 25, 2010 #3
    First integrate it, then you get [-e-x] from 0 to infinity.

    The key is to find the limit as x approaches infinity of (-e-x).

    (Hint: Put in a very large negative value for x and see what you get.)
     
  5. Mar 25, 2010 #4
    sorry ..~ i missed out the negative ..~
    now i know already ..~ tq tq ...
     
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