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Homework Help: Improper Integral

  1. Feb 26, 2010 #1
    How the following limit can be zero, since after applying L'Hospital rule the root x will be in the numerator, which together with sinx will constitute infinity.
     

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  2. jcsd
  3. Feb 26, 2010 #2

    Dick

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    I'm not sure you are actually using the product rule correctly. Hard to tell since you don't show what you actually did. But you have an x in the denominator. It's still infinity/infinity.
     
  4. Feb 26, 2010 #3
    The proceedure is following, In my book they have equate it to zero.
     

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  5. Feb 27, 2010 #4

    Dick

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    Your limit is completely wrong, the limit is 0. (1-cos(x))/x^1/2 goes to zero. Why do you think it doesn't? (1-cos(x)) is bounded. x^(1/2) isn't.
     
  6. Feb 27, 2010 #5
    Oh, I got it. Thanks a lot.
     
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