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Homework Help: Find the limit

  1. Apr 13, 2010 #1
    1. The problem statement, all variables and given/known data

    Find the limit,

    [tex] f(r) = \frac{r}{\sqrt{1+r^{2}}} [/tex]



    2. Relevant equations

    None.


    3. The attempt at a solution

    I attempted to multiply both the top and bottom of the above equation by the denominator to cancel out the square root on the denominator, but this doens't seem to help.

    Any ideas?
     
    Last edited: Apr 13, 2010
  2. jcsd
  3. Apr 13, 2010 #2

    Dick

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    The limit as r approaches what?
     
  4. Apr 13, 2010 #3
    Can't edit it correctly above, the correct problem statement is,

    [tex]\[ \lim_{r \to +\infty} \frac{r}{\sqrt{1+r^{2}}}\] [/tex]
     
  5. Apr 13, 2010 #4

    Dick

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    Multiply numerator and denominator by 1/r. Move the 1/r inside the radical in the denominator by squaring it. What does it look like now?
     
  6. Apr 13, 2010 #5
    Got it, thanks!
     
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