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: L'ptsle's rule (spelt wrong)

  1. Dec 1, 2007 #1
    It works for 0/0 or infinity/infinity

    Does it work for -infinity/infinity? wiki suggests no.

    Books give examples for lim xln(x) and does it and appplies this rule. HOwever it's really -infinity/infinity!
  2. jcsd
  3. Dec 1, 2007 #2

    Gib Z

    User Avatar
    Homework Helper

    Of course it works for -infinity/infinity! Thats because (if and only if the limit exists) [tex] \lim_{x\to a} - f(x) = - \lim_{x\to a} f(x)[/tex]. The second part is one of the cases you know it works.
  4. Dec 1, 2007 #3


    User Avatar
    Staff Emeritus
    Science Advisor

    Are you talking about l'Hopital, or l'Hospital's rule? If so, that is a weird spelling in the title!
  5. Dec 1, 2007 #4
    LOL! Damn ... I've never seen it butchered that badly. Good laugh, thanks :-] no offense either :p
    Last edited: Dec 1, 2007
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook