Results 1 to 2 of 2

Math Help - interpreting a function

  1. #1
    Junior Member
    Joined
    May 2009
    Posts
    68

    interpreting a function

    I do not know how to do this question
    Consider the function f(x) = [(2x-a)(x-b)]/[5(x-b)(x-c)] . Determine where the following features of its graph are located in terms of a, b, and/or c. Explain your reasoning for each situation.

    a. the x-intercepts

    b. the y-intercepts

    c. any vertical asymptotes

    d. any horizontal asymptotes

    e. any “holes” in the graph

    How do I find a b c d and e? does graphing it out make it easier? or are there formulas to use as well?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Mar 2010
    From
    Florida
    Posts
    3,093
    Thanks
    5
    Quote Originally Posted by foreverbrokenpromises View Post
    I do not know how to do this question
    Consider the function f(x) = [(2x-a)(x-b)]/[5(x-b)(x-c)] . Determine where the following features of its graph are located in terms of a, b, and/or c. Explain your reasoning for each situation.

    a. the x-intercepts

    b. the y-intercepts

    c. any vertical asymptotes

    d. any horizontal asymptotes

    e. any “holes” in the graph

    How do I find a b c d and e? does graphing it out make it easier? or are there formulas to use as well?
    a. For x intercepts, we need to find points in the form (x,0) so lets do that.
    f(x)=\frac{(2x-a)(x-b)}{5(x-b)(x-c)}=0\rightarrow (2x-a)(x-b)=2x^2-x(2b+a)+ab =(x-b)(2x-a)=0
    You can finish it.

    b. For y intercepts, we need to find points in the form (0,y).
    f(0)=\frac{(2*0-a)(0-b)}{5(0-b)(0-c)}=\frac{ab}{5bc}

    c. Vertical asymptotes will happen the fraction is undefined \frac{x}{0}
    5(x-b)(x-c)=0\rightarrow x=b,c

    d. For this, we need to run the limits.
    \lim_{x\to\infty}\frac{(2x-a)(x-b)}{5(x-b)(x-c)}\rightarrow \frac{2x^2}{5x^2}=\frac{2}{5}

    e. This is actually giving to you since we are giving the fractions factored. This occurs when x=b
    Last edited by dwsmith; May 18th 2010 at 08:20 PM. Reason: Forgot the 5
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Interpreting generalised momenta
    Posted in the Advanced Applied Math Forum
    Replies: 2
    Last Post: January 15th 2012, 09:01 AM
  2. Need help Interpreting Vertical Intercept
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: February 17th 2010, 10:32 PM
  3. Interpreting Logistic Results
    Posted in the Advanced Statistics Forum
    Replies: 0
    Last Post: August 15th 2009, 04:29 AM
  4. Interpreting Limits
    Posted in the Calculus Forum
    Replies: 5
    Last Post: August 5th 2009, 08:25 AM
  5. Interpreting Dif EQ
    Posted in the Calculus Forum
    Replies: 0
    Last Post: November 14th 2007, 05:32 PM

Search Tags


/mathhelpforum @mathhelpforum