Results 1 to 7 of 7

Math Help - Sketching a function-- please help

  1. #1
    Newbie
    Joined
    Mar 2008
    Posts
    5

    Sketching a function-- please help

    Sketch the following function from the description given below.

    x= -1 and y= 2 are asymptotes.
    The y intercept is 3 and the x intercept is -1.5
    As x -> infinity, y -> 2
    As x -> negative infinity, y -> 2
    As x tends to -1 from below, y -> negative infinity and as x tends to -1 from above, y -> infinity.


    Help will be greatly appreciated
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    earboth's Avatar
    Joined
    Jan 2006
    From
    Germany
    Posts
    5,830
    Thanks
    123
    Quote Originally Posted by needmathshelp1234 View Post
    Sketch the following function from the description given below.

    x= -1 and y= 2 are asymptotes.
    The y intercept is 3 and the x intercept is -1.5
    As x -> infinity, y -> 2
    As x -> negative infinity, y -> 2
    As x tends to -1 from below, y -> negative infinity and as x tends to -1 from above, y -> infinity.

    ...
    1. Draw the asymptotes and mark those parts of the coordinate system where the graph of the function never can be.

    2. Draw a smooth curve to the asymptotes in the "allowed" areas.

    3. From the vertical asymptote you know that the denominator must contain the factor (x+1).
    From the horizontal asymptote you know that the numerator must contain the factor (2x+3).

    4. I've sketched the function f(x) = \frac{2x+3}{x+1} which obviously satisfies all given conditions.
    Attached Thumbnails Attached Thumbnails Sketching a function-- please help-simpl_gebrfkt.jpg  
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by needmathshelp1234 View Post
    Sketch the following function from the description given below.

    x= -1 and y= 2 are asymptotes.
    The y intercept is 3 and the x intercept is -1.5
    As x -> infinity, y -> 2
    As x -> negative infinity, y -> 2
    As x tends to -1 from below, y -> negative infinity and as x tends to -1 from above, y -> infinity.


    Help will be greatly appreciated
    This question was answered here. What has prompted you to ask it again?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Mar 2008
    Posts
    5
    The answer you posted in my first post made no sense to me. I though I would be polite and thankyou, hence my need to repost the question.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by needmathshelp1234 View Post
    The answer you posted in my first post made no sense to me. I though I would be polite and thankyou, hence my need to repost the question.
    Fair enough. But all you had to do was say so.

    What in particular made no sense ....? Was it that you couldn't see where the equation came from? Or that you couldn't see how the equation satisfied the given requireements of the question. Or was it that you didn't know how to sketch a (rectangular) hyperbola.

    You'll learn a lot more by following through on such things rather than posting again .....

    Note for the future: You will not hurt my feelings (and most probably you won't hurt the feelings of 99.9% of the members of this forum) if you do as I've suggested.
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Newbie
    Joined
    Mar 2008
    Posts
    5
    Quote Originally Posted by mr fantastic View Post
    Fair enough. But all you had to do was say so.

    What in particular made no sense ....? Was it that you couldn't see where the equation came from? Or that you couldn't see how the equation satisfied the given requireements of the question. Or was it that you didn't know how to sketch a (rectangular) hyperbola.

    You'll learn a lot more by following through on such things rather than posting again .....

    Note for the future: You will not hurt my feelings (and most probably you won't hurt the feelings of 99.9% of the members of this forum) if you do as I've suggested.
    Ok I will take that into consideration... thanks. I just was fully confused on the whole concept as we haven't really learnt it the way your equation was. But thanks anyway. When I draw my graph, do I put arrows on the end? Like the domain and range go to infinity?
    Thanks
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by needmathshelp1234 View Post
    Ok I will take that into consideration... thanks. I just was fully confused on the whole concept as we haven't really learnt it the way your equation was. But thanks anyway. When I draw my graph, do I put arrows on the end? Like the domain and range go to infinity?
    Thanks
    When the domain and range go to infinity, yes you should. Otherwise it might look like you think there are finite endpoints ....
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Help Sketching a function
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: December 13th 2011, 04:35 PM
  2. Sketching of modulus function
    Posted in the Algebra Forum
    Replies: 4
    Last Post: December 27th 2010, 05:45 AM
  3. sketching a function
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: September 14th 2009, 06:13 PM
  4. Sketching a function ????
    Posted in the Calculus Forum
    Replies: 4
    Last Post: April 16th 2008, 06:18 AM
  5. Sketching a function-- please help
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: March 14th 2008, 02:22 AM

Search Tags


/mathhelpforum @mathhelpforum