Results 1 to 3 of 3

Thread: vertical asymptotes

  1. #1
    Newbie
    Joined
    Jun 2006
    Posts
    14

    pretest 6 math questions

    Find the horizontal asymptote of the graph f(x)= 2/x-4

    A: y=2 B: x=0 C: x=4 D: y=0

    Find the vertical asymptote(s) if any, for f(x)= 4x-4/x2-5x-6

    A: x=-1, x=6, x=4 B: x=-1, x=6 C: x=4, x=-1 D: none

    Find the zeros of the function. F(x)= 4x-7/x-2
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    10
    Quote Originally Posted by Lane
    Find the horizontal asymptote of the graph f(x)= 2/x-4

    A: y=2 B: x=0 C: x=4 D: y=0
    At this level it is when the denominator is zero. Thus, if you mean $\displaystyle y=\frac{2}{x}-4$ then the answer is $\displaystyle x=0$ and if you mean $\displaystyle y=\frac{2}{x-4}$ then the answer is $\displaystyle x=4$
    Quote Originally Posted by Lane
    Find the vertical asymptote(s) if any, for f(x)= 4x-4/x2-5x-6

    A: x=-1, x=6, x=4 B: x=-1, x=6 C: x=4, x=-1 D: none
    Factor
    $\displaystyle \frac{4(x-1)}{(x+1)(x-6)}$ that happens when $\displaystyle x=-1,6$ (remember set each factor equal to zero).


    Quote Originally Posted by Lane
    Find the zeros of the function. F(x)= 4x-7/x-2
    You need an "x" such as,
    $\displaystyle \frac{4x-7}{x-2}$ a fraction is only zero when its numerator is zero thus,
    $\displaystyle 4x-7=$ thus, $\displaystyle x=7/4=1.75$
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member
    earboth's Avatar
    Joined
    Jan 2006
    From
    Germany
    Posts
    5,854
    Thanks
    138
    Quote Originally Posted by Lane
    Find the horizontal asymptote of the graph f(x)= 2/x-4

    A: y=2 B: x=0 C: x=4 D: y=0...
    Hello,Lane,

    you'll get the horizontal asymptote if calculate the limit of f(x):

    a) you mean: $\displaystyle f(x)=\frac{2}{x}-4$. Then $\displaystyle \lim_\csub{|x|\rightarrow\infty} f(x)=-4\ \Longrightarrow\ As: y = -4$

    b) you mean: $\displaystyle f(x)=\frac{2}{x-4}$. then $\displaystyle \lim_\csub{|x|\rightarrow\infty} f(x)=0\ \Longrightarrow\ As: y = 0$

    The possible answers doesn't include y = -4, therefore the answer is D.

    Greetings

    EB
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. vertical asymptotes?
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: Apr 14th 2010, 04:31 PM
  2. Vertical Asymptotes
    Posted in the Calculus Forum
    Replies: 2
    Last Post: Oct 4th 2009, 05:53 PM
  3. Vertical Asymptotes?
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: Sep 28th 2009, 03:17 PM
  4. Vertical Asymptotes
    Posted in the Calculus Forum
    Replies: 1
    Last Post: Sep 23rd 2009, 12:45 PM
  5. Vertical Asymptotes
    Posted in the Pre-Calculus Forum
    Replies: 4
    Last Post: Jul 17th 2009, 07:22 PM

Search Tags


/mathhelpforum @mathhelpforum