Results 1 to 7 of 7

Math Help - determaining trig equations

  1. #1
    Newbie
    Joined
    Jan 2008
    Posts
    4

    determaining trig equations

    when refering to a graph...how do you find the horizontial translation? i know you use sin or cosine but i dont understand the method very clearly. can someone clarify this?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Happy1234 View Post
    when refering to a graph...how do you find the horizontial translation? i know you use sin or cosine but i dont understand the method very clearly. can someone clarify this?
    If you have y = a \sin (bx + c) + d the horizontal shift is given by d. Similarly for cos.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Jan 2008
    Posts
    4
    thanks for responding..however that wasnt exactly my question. iunderstand that d is equal to the H.T. but if from interpreting a graph i have to find the equation. how do i find Horizotial translation....
    Follow Math Help Forum on Facebook and Google+

  4. #4
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    Quote Originally Posted by mr fantastic View Post
    If you have y = a \sin (bx + c) + d the horizontal shift is given by d. Similarly for cos.
    Quote Originally Posted by Happy1234 View Post
    thanks for responding..however that wasnt exactly my question. iunderstand that d is equal to the H.T.
    actually, d gives the vertical shift

    the horizontal shift is given by: - \frac cb in this form...

    i prefer the form: y = a \sin k(x - b) + c


    but if from interpreting a graph i have to find the equation. how do i find Horizotial translation....
    well, know where the graphs should begin and track where they shifted to. for instance, you know that sin(0) = 0. so if you have a function that you are interpreting to be a sine graph and you see that sin(0) = 1, say, you know the shift will be - \frac {\pi}2 since you would see that \sin \left( - \frac {\pi}2 \right) = 0 for that graph. things like that
    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 Happy1234 View Post
    thanks for responding..however that wasnt exactly my question. iunderstand that d is equal to the H.T. but if from interpreting a graph i have to find the equation. how do i find Horizotial translation....
    First off: Whoops ... my mistake. I gave the vertical shift ...... The horizontal shift is given by -c/b.


    As far as looking at a graph is concerned, you can get the horizontal shift by looking at where a simple turning point should be without any shift (for y = sin x there's a max turning point at 90 degrees, for y = cos x there's a max turning point at x = 0) and then seeing how far it has been shifted ....
    Follow Math Help Forum on Facebook and Google+

  6. #6
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    Quote Originally Posted by mr fantastic View Post
    As far as looking at a graph is concerned, you can get the horizontal shift by looking at where a simple turning point should be without any shift (for y = sin x there's a max turning point at 90 degrees, for y = cos x there's a max turning point at x = 0) and then seeing how far it has been shifted ....
    that is perhaps a better way to look for it
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Newbie
    Joined
    Jan 2008
    Posts
    4
    thanks so much!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Trig Equations
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: February 24th 2009, 11:08 AM
  2. trig equations
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 17th 2008, 05:22 AM
  3. Trig Equations with Multiple Trig Functions cont.
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: April 7th 2008, 06:50 PM
  4. Trig Equations with Multiple Trig Functions help
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 6th 2008, 06:48 PM
  5. Trig Equations with Multiple Trig Functions
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 6th 2008, 04:48 PM

Search Tags


/mathhelpforum @mathhelpforum