1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Simple limit

  1. Mar 9, 2009 #1
    1. The problem statement, all variables and given/known data

    lim x->0 (n/log(n))[n1/n-1]

    3. The attempt at a solution

    I've just been trying to move things around, and use L'Hospitals when appropriate. I haven't been able to see the trick.

    Got any hints?
  2. jcsd
  3. Mar 9, 2009 #2
    Try the algebra of limits
  4. Mar 9, 2009 #3
    Do you mean lim n->infinity?
  5. Mar 10, 2009 #4
    woops, ya as n goes to infinity.

    Ive been using L'hospitals on the numerator after multiplying the n through and rewriting in exponential form.

    d/dx:[x1/x+1-x] = d/dx:[e(1/x+1)ln(x)-x]= e(1/x+1)ln(x)( -ln(x)/x2+(x+1)/x2) -1
    and the bottom goes to 1/x

    so the new limit after applying L'Hospital is
    e(1/x+1)ln(x)((x+1)-ln(x)/x) -x

    which leaves me with a big question mark.
  6. Mar 10, 2009 #5
    also tried looking at it like this.


    using L'H on the top and bottom give:

    x1/x((1-ln(x)/x2)/(1-log(x))... I want to do something with that log
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook