Page 1 of 2 12 LastLast
Results 1 to 15 of 23

Math Help - Very difficult problem (transformation of functions)

  1. #1
    Newbie
    Joined
    Apr 2010
    Posts
    10

    Very difficult problem (transformation of functions)

    The problem states;
    The graph of y=f(x) is given. Match each equation with its graph.
    a) y=f(x-4)
    b)y=2f(x+6)
    c)y=f(x)+3
    d)y=-f(2x)

    What I find confusing is that these are parabolas. Why is this?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Master Of Puppets
    pickslides's Avatar
    Joined
    Sep 2008
    From
    Melbourne
    Posts
    5,236
    Thanks
    29
    Quote Originally Posted by ibrahimovic9 View Post
    The problem states;
    The graph of y=f(x) is given. Match each equation with its graph.
    a) y=f(x-4)
    b)y=2f(x+6)
    c)y=f(x)+3
    d)y=-f(2x)

    What I find confusing is that these are parabolas. Why is this?
    What are we matching these equations to? You don't have enough information here.

    Given y= f(x) is transformed to y=a\times f(x-h)+k

    a is a dilation factor away from the y axis, h is a horizontal shift and k a vertical shift.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Apr 2010
    Posts
    10
    sorry. Heres a link to a more descriptive analysis of the type of problem. Same instructions but different problem. It is problem number 4. The problem is in page 2.
    http://www.farmingdale.edu/CampusPag..._Functions.pdf


    http://www.farmingdale.edu/CampusPag..._Functions.pdf
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Senior Member
    Joined
    Oct 2009
    From
    Brisbane
    Posts
    311
    Thanks
    2
    Quote Originally Posted by ibrahimovic9 View Post
    The problem states;
    The graph of y=f(x) is given. Match each equation with its graph.
    a) y=f(x-4)
    b)y=2f(x+6)
    c)y=f(x)+3
    d)y=-f(2x)

    What I find confusing is that these are parabolas. Why is this?
    The original graph of y=f(x) could be anything - in this case it is a parabola.

    The question relates to transforming the original graph (whatever shape it is). There are basically 4 types of transformations:
    y= a*f(x)
    y=f(b*x)
    y=f(x -c)
    y=f(x) +d
    The a, b, c, and d have different effects on the original graph of y=f(x).
    Do you know what these effects are?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Apr 2010
    Posts
    10
    i dont know what these effects might be. The info I am giving you is the info shown to me. If you can see the link i posted. Appreciate all the help
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Senior Member
    Joined
    Oct 2009
    From
    Brisbane
    Posts
    311
    Thanks
    2
    Quote Originally Posted by ibrahimovic9 View Post
    i dont know what these effects might be. The info I am giving you is the info shown to me. If you can see the link i posted. Appreciate all the help
    I can help you get a better understanding of this. Have you got a graphics calculator handy?
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Newbie
    Joined
    Apr 2010
    Posts
    10
    yes i do. I have typed in the equation y= f(x-4) but all i get is a straight line.
    Follow Math Help Forum on Facebook and Google+

  8. #8
    Junior Member
    Joined
    Jan 2010
    Posts
    49
    answer :

    4 a) 2
    b) ???
    c) 1
    d) 4

    for 4 b) the equation is y = -f(x+4)

    rearrange the equation become y = -f(x-(-4)) which is in standard form..

    thus the graph of f(x) should be reflected across x-axis and shifted horizotally 4 unit to the left...


    the graph for number 3 is -f(x+4)-1...
    Follow Math Help Forum on Facebook and Google+

  9. #9
    Senior Member
    Joined
    Oct 2009
    From
    Brisbane
    Posts
    311
    Thanks
    2
    Quote Originally Posted by ibrahimovic9 View Post
    yes i do. I have typed in the equation y= f(x-4) but all i get is a straight line.
    You need to understand what is going on here.
    I think you probably typed in y=x-4 which IS a straight line, but that's irrelevant here.

    I'll take you through the steps.
    On your GC draw the parabola y=x^2 for starters. (You could do this with any graph but lets start with a basic parabola)
    Follow Math Help Forum on Facebook and Google+

  10. #10
    Newbie
    Joined
    Apr 2010
    Posts
    10
    ok. i got that
    next?
    Follow Math Help Forum on Facebook and Google+

  11. #11
    Junior Member
    Joined
    Jan 2010
    Posts
    49
    Quote Originally Posted by ibrahimovic9 View Post
    yes i do. I have typed in the equation y= f(x-4) but all i get is a straight line.
    of course it will yield a straight line because you did nit define the function of f(x) is... since what you type is y= f(x-4) for sure it will sketch a straight line... try to the get the equation for the parabola shown in the figure... the substitute in the equation... the only you can sketch the parabola
    Follow Math Help Forum on Facebook and Google+

  12. #12
    Senior Member
    Joined
    Oct 2009
    From
    Brisbane
    Posts
    311
    Thanks
    2
    Quote Originally Posted by ibrahimovic9 View Post
    ok. i got that
    next?
    Good, bear with me and you'll be an expert in no time!!

    Keep the graph of y=x^2 and now also graph y=2*x^2. y=3*x^2
    Follow Math Help Forum on Facebook and Google+

  13. #13
    Newbie
    Joined
    Apr 2010
    Posts
    10
    got it
    Follow Math Help Forum on Facebook and Google+

  14. #14
    Senior Member
    Joined
    Oct 2009
    From
    Brisbane
    Posts
    311
    Thanks
    2
    Quote Originally Posted by ibrahimovic9 View Post
    got it
    OK so what is the effect of multiplying by 2 and then 3. What happens to the original graph?
    Follow Math Help Forum on Facebook and Google+

  15. #15
    Newbie
    Joined
    Apr 2010
    Posts
    10
    it shrinks
    Follow Math Help Forum on Facebook and Google+

Page 1 of 2 12 LastLast

Similar Math Help Forum Discussions

  1. Transformation of functions
    Posted in the Algebra Forum
    Replies: 2
    Last Post: March 25th 2011, 11:30 AM
  2. Trig functions (very difficult)
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: April 27th 2010, 10:36 AM
  3. Replies: 2
    Last Post: May 22nd 2009, 12:43 PM
  4. Replies: 2
    Last Post: February 15th 2009, 05:42 AM
  5. Hyperbolic Functions (not difficult)
    Posted in the Calculus Forum
    Replies: 1
    Last Post: October 31st 2008, 07:16 PM

Search Tags


/mathhelpforum @mathhelpforum