Results 1 to 2 of 2

Math Help - Domain of Rational Functions

  1. #1
    Newbie
    Joined
    Jan 2007
    Posts
    10

    Domain of Rational Functions

    First of all, what is a rational function?

    Secondly, how do I find the domain of rational functions?

    Find the domain of each rational function below.

    [1] Q(x) = -x(1 - x)/(3x^2 +5x -2)

    [2] F(x) = -2(x^2 - 4)/3(x^2 + 4x + 4)
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    9
    Quote Originally Posted by fdrhs View Post
    [SIZE="3"]First of all, what is a rational function?
    A rational function is a function of a quotient (fraction) of two polynomial functions.
    Secondly, how do I find the domain of rational functions?
    The "bad" points are where the denominator is zero.
    Find the domain of each rational function below.

    [1] Q(x) = -x(1 - x)/(3x^2 +5x -2)
    Again the denominator is not zero.
    Thus,
    3x^2+5x-2=0
    Find those x.
    And then the domain is all x EXCEPT the ones you found just above.

    Same approach to other problem.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Domain of a rational function
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: August 27th 2011, 07:42 PM
  2. domain of functions 1
    Posted in the Algebra Forum
    Replies: 4
    Last Post: January 21st 2010, 12:29 PM
  3. domain of functions 4
    Posted in the Algebra Forum
    Replies: 6
    Last Post: January 21st 2010, 12:24 PM
  4. Replies: 4
    Last Post: March 27th 2009, 08:19 PM
  5. Determine the domain of a rational function
    Posted in the Pre-Calculus Forum
    Replies: 5
    Last Post: June 30th 2008, 04:56 PM

Search Tags


/mathhelpforum @mathhelpforum