Results 1 to 6 of 6

Math Help - Finding the domain of a function

  1. #1
    Newbie
    Joined
    Feb 2008
    Posts
    9

    Finding the domain of a function

    g(x)=\sqrt{x+1/x}

    I am trying to get the answer for this. What I got is (-inf,+inf). Is this right?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,798
    Thanks
    1691
    Awards
    1
    Which of these functions is it? <br />
g_1 (x) = \sqrt {x + \frac{1}{x}} \,\mbox{ or } \,g_2 (x) = \sqrt {\frac{{x + 1}}{x}}
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Feb 2008
    Posts
    9
    The first one.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,798
    Thanks
    1691
    Awards
    1
    Quote Originally Posted by Mortifix View Post
    The first one.
    Well O.K.
    x + \frac{1}{x} = \frac{{x^2  + 1}}{x} \ge 0\quad  \Rightarrow \quad x > 0
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Feb 2008
    Posts
    9
    Ok so how would I write that in set builder notation. What it be (-inf,0]U[0,inf+)?
    Follow Math Help Forum on Facebook and Google+

  6. #6
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,798
    Thanks
    1691
    Awards
    1
    Quote Originally Posted by Mortifix View Post
    Ok so how would I write that in set builder notation. What it be (-inf,0]U[0,inf+)?
    \left\{ {x \in \mathbb{R}:x > 0} \right\} = \left( 0 \right.,\left. \infty  \right)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Finding domain of function
    Posted in the Pre-Calculus Forum
    Replies: 7
    Last Post: November 12th 2011, 06:16 AM
  2. Finding the domain of a function.
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: November 7th 2011, 06:44 PM
  3. Finding domain of a function!
    Posted in the Algebra Forum
    Replies: 6
    Last Post: September 10th 2010, 09:04 AM
  4. Finding the domain of this function?
    Posted in the Algebra Forum
    Replies: 3
    Last Post: September 11th 2008, 02:16 AM
  5. Finding the domain of a function
    Posted in the Pre-Calculus Forum
    Replies: 6
    Last Post: January 30th 2008, 03:51 PM

Search Tags


/mathhelpforum @mathhelpforum