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: Brief, basic - lim question

  1. Oct 30, 2007 #1
    Brief, basic -- lim question...

    So, i know this is too basic, but can anyone tell me what the lim of ln(x) is as x approaches
    -neg infinity
    -zero (from left and right)

    --> I know I am supposed to know these, but I think I might be confusing them...

    Thank you!
  2. jcsd
  3. Oct 30, 2007 #2
    You can do this analytically, just by visualizing the graph of the function.
    -As x increases, the natural log of x also increases without bound.
    -Are negative numbers part of your domain?
    -What happens to values of ln(x) as x approaces 0? Just look at a graph of the parent function.
  4. Oct 30, 2007 #3
    I wouldn't call that analytic. I would think of ln(x) as the inverse of exp(x) and exp(x) has derivative strictly greater than 1 for all x>0.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook