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  1. #1
    Junior Member nouras's Avatar
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    Limit as x approaches infinity of xsin(1/x)?

    i know it is 1 but, i dont know how to get there..

  2. #2
    Junior Member Depressed's Avatar
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    lim x --> inf (xsin(1/x))
    lim x --> inf (sin(1/x)/ 1/x)
    lim x --> inf ((-1/x^2)cos(1/x)/ -1/x^2)
    lim x ---> inf (cos(1/x))

    cos(1/infinity) ~ cos(0) = 1

  3. #3
    Junior Member supastremph's Avatar
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    xsin(1/x) = sin(1/x)/(1/x)

    by l'hopital's rule: lim = lim cos(1/x)ln(x)/lnx = lim cos(1/x) = 1, since cos(0) =1.


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