Results 1 to 3 of 3

Math Help - Limits at Infinity

  1. #1
    Newbie
    Joined
    Oct 2009
    Posts
    6

    Limits at Infinity

    Lim {x - > ∞ } (x - √x^2 + x)



    Evaluate the Limit
    Follow Math Help Forum on Facebook and Google+

  2. #2
    -1
    e^(i*pi)'s Avatar
    Joined
    Feb 2009
    From
    West Midlands, England
    Posts
    3,053
    Thanks
    1
    Quote Originally Posted by valeriegriff View Post
    Lim {x - > ∞ } (x - √x^2 + x)



    Evaluate the Limit
    Either I've missed something or the question is wrong:

    x - \sqrt{x^2} + x = x-x+x = 2x-x = x

    so the limit would be \infty
    Last edited by e^(i*pi); October 1st 2009 at 01:14 PM. Reason: ******* latex
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Senior Member DeMath's Avatar
    Joined
    Nov 2008
    From
    Moscow
    Posts
    473
    Thanks
    5
    Quote Originally Posted by valeriegriff View Post
    Lim {x - > ∞ } (x - √x^2 + x)


    Evaluate the Limit
    \mathop {\lim }\limits_{x \to \infty } \left( {x - \sqrt {{x^2} + x} } \right) = \mathop {\lim }\limits_{x \to \infty } \frac{{\left( {x - \sqrt {{x^2} + x} } \right)\left( {x + \sqrt {{x^2} + x} } \right)}}<br />
{{x + \sqrt {{x^2} + x} }} =

    =  - \mathop {\lim }\limits_{x \to \infty } \frac{x}<br />
{{x + \sqrt {{x^2} + x} }} =  - \mathop {\lim }\limits_{x \to \infty } \frac{1}<br />
{{1 + \sqrt {1 + \frac{1}<br />
{{{x^2}}}} }} =  - \frac{1}<br />
{{1 + \sqrt {1 + 0} }} =  - \frac{1}<br />
{2}.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Limits at infinity
    Posted in the Calculus Forum
    Replies: 3
    Last Post: February 16th 2010, 05:17 PM
  2. limits toward neg. infinity
    Posted in the Calculus Forum
    Replies: 4
    Last Post: December 17th 2009, 01:56 PM
  3. Limits at Infinity
    Posted in the Calculus Forum
    Replies: 1
    Last Post: November 14th 2009, 10:56 PM
  4. limits to infinity
    Posted in the Calculus Forum
    Replies: 1
    Last Post: November 14th 2009, 04:38 PM
  5. Limits at Infinity
    Posted in the Pre-Calculus Forum
    Replies: 15
    Last Post: October 14th 2009, 06:02 PM

Search Tags


/mathhelpforum @mathhelpforum