Results 1 to 5 of 5

Math Help - Evaluate the limit

  1. #1
    Newbie
    Joined
    Jan 2010
    Posts
    2

    Evaluate the limit

    Evaluate the limit of 4-x/2-√x as x approaches 4

    I believe that this function is in indeterminate form. I just cant seem to rewrite the function so that i can find the limit ( if it exists).

    If anyone can explain how to evaluate this limit, I would be very grateful.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor Bruno J.'s Avatar
    Joined
    Jun 2009
    From
    Canada
    Posts
    1,266
    Thanks
    1
    Awards
    1
    You should use parentheses to write this expression. It could mean at least 4 different things, but as stated it means 4-\frac x 2 - \sqrt x.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member
    Joined
    Jun 2009
    From
    United States
    Posts
    676
    Thanks
    19
    Quote Originally Posted by mj226 View Post
    Evaluate the limit of 4-x/2-√x as x approaches 4

    I believe that this function is in indeterminate form. I just cant seem to rewrite the function so that i can find the limit ( if it exists).

    If anyone can explain how to evaluate this limit, I would be very grateful.
    Multiply by \frac{2+\sqrt{x}}{2+\sqrt{x}}

    \lim_{x->4}\frac{4-x}{2-\sqrt{x}}\left(\frac{2+\sqrt{x}}{2+\sqrt{x}}\right  )=\lim_{x->4}\frac{(4-x)(2+\sqrt{x})}{4-x}

    =\lim_{x->4}(2+\sqrt{x})

    =4
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Jan 2010
    Posts
    2
    Sorry about the parentheses. It should have been (4-x)/(2-x^1/2)


    Oh. I see. Thank You.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Super Member General's Avatar
    Joined
    Jan 2010
    From
    Kuwait
    Posts
    562
    Quote Originally Posted by mj226 View Post
    Sorry about the parentheses. It should have been (4-x)/(2-x^1/2)


    Oh. I see. Thank You.
    There is another one.
    4-x=(2)^2-(\sqrt{x})^2=(2-\sqrt{x})(2+\sqrt{x})
    Bad guys cancel, and you are done.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Evaluate the following limit
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: May 6th 2010, 09:36 AM
  2. Evaluate The Following Limit. (3)
    Posted in the Calculus Forum
    Replies: 1
    Last Post: February 16th 2010, 06:53 AM
  3. How do you evaluate a limit
    Posted in the Calculus Forum
    Replies: 2
    Last Post: November 2nd 2009, 09:37 AM
  4. evaluate the limit
    Posted in the Calculus Forum
    Replies: 1
    Last Post: October 19th 2009, 06:01 PM
  5. To Evaluate the following limit...
    Posted in the Calculus Forum
    Replies: 1
    Last Post: April 6th 2009, 12:06 PM

Search Tags


/mathhelpforum @mathhelpforum