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: Question about a limit

  1. Sep 28, 2011 #1
    x[itex]\stackrel{Lim}{\rightarrow}[/itex]infinity ([itex]\sqrt{x^{2}+1}[/itex])[itex]-1[/itex]

    Couldn't I just inset 0 for x and end up getting [itex]\sqrt{1}[/itex]?

    The book tells me to rewrite this problem by its conjugate.

    My question is why? Thanks
    Last edited: Sep 28, 2011
  2. jcsd
  3. Sep 28, 2011 #2


    Staff: Mentor

    As you have written it,
    [tex]\lim_{x \to \infty}\sqrt{x^2 + 1} - 1 = \infty[/tex]
    You seem to be a little confused in this problem. Why would you put in zero for x when the limit is as x goes to infinity?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook