Results 1 to 4 of 4

Math Help - l'hopital rule

  1. #1
    Junior Member
    Joined
    Jun 2009
    Posts
    61

    l'hopital rule

    hi... first thread here...

    my question is regarding l'hopital rule.

    i understand the rule is applicable only if both limits -
    of f(x) and g(x) when were looking for lim of f(x)/g(x)
    are identical and go to infinity, -infinity or 0.

    my question is what if one limit is infinity, and the other -inifinty...
    is there any way to go around that, or that means the limit does not exist?

    thanks in advance.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    skeeter's Avatar
    Joined
    Jun 2008
    From
    North Texas
    Posts
    12,115
    Thanks
    992
    Quote Originally Posted by vonflex1 View Post
    hi... first thread here...

    my question is regarding l'hopital rule.

    i understand the rule is applicable only if both limits -
    of f(x) and g(x) when were looking for lim of f(x)/g(x)
    are identical and go to infinity, -infinity or 0.

    my question is what if one limit is infinity, and the other -inifinty...
    is there any way to go around that, or that means the limit does not exist?

    thanks in advance.
    -1 is a constant that can be factored out of the limit
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Senior Member Spec's Avatar
    Joined
    Aug 2007
    Posts
    318
    The rule actually says that \lim_{x\to c}f(x)=\pm  \lim_{x\to c}g(x)=\pm \infty

    So no, it's not a problem.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Junior Member
    Joined
    Jun 2009
    Posts
    61
    thanks!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. L' Hopital's Rule
    Posted in the Calculus Forum
    Replies: 3
    Last Post: February 26th 2010, 12:08 PM
  2. L'Hopital's Rule
    Posted in the Calculus Forum
    Replies: 4
    Last Post: July 28th 2009, 06:40 PM
  3. líHopitalís Rule Help..
    Posted in the Calculus Forum
    Replies: 5
    Last Post: March 28th 2009, 12:06 AM
  4. L'hopital Rule qn
    Posted in the Calculus Forum
    Replies: 2
    Last Post: August 26th 2008, 11:36 AM
  5. L'Hopital Rule
    Posted in the Calculus Forum
    Replies: 3
    Last Post: August 8th 2008, 05:00 PM

Search Tags


/mathhelpforum @mathhelpforum