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Homework Help: Find the limit of xsin(pi*x) at infinity

  1. Feb 23, 2005 #1
    Since the function f(x)=xsin[(pi)x] oscillates, shouldnt the limit as x -> infinity not exist? i was told that it is positive infinity.
     
  2. jcsd
  3. Feb 23, 2005 #2

    arildno

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    If your function really is [tex]f(x)=x\sin(\pi{x})[/tex] , then you're right.
    (That is, a limit doesn't exist)
     
    Last edited: Feb 23, 2005
  4. Feb 23, 2005 #3

    dextercioby

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    Note,that "pi" in the argument is totally unimportant.A certain rescaling would eliminate it...:wink:

    Daniel.
     
  5. Feb 23, 2005 #4

    arildno

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    Unless, of course, x is supposed to be an integer variable; in which case a limit does exist..:wink:
     
  6. Feb 23, 2005 #5

    dextercioby

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    Of course,Arildno,mathematicians thought of it and decided to use the "n" (middle Latin alphabet letters,in general) for the INTEGER/natural numbers.Just the same way as "x" stands for reals and "z" for complex...:wink:


    Daniel.
     
  7. Feb 23, 2005 #6

    arildno

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    I'll just post for a face change..:smile:
     
  8. Feb 23, 2005 #7

    dextercioby

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    No face change needed...I can handle "winks"...:wink:

    Daniel.
     
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