Results 1 to 5 of 5

Math Help - Periodic functions

  1. #1
    Member
    Joined
    Jul 2010
    Posts
    85

    Periodic functions

    see attached
    Attached Files Attached Files
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member BAdhi's Avatar
    Joined
    Oct 2010
    From
    Gampaha, Sri Lanka
    Posts
    252
    Thanks
    6
    a)check out my definitions, please mention if they are wrong..
    amplitude is the distant between a max and min (i.e. 4.5-1 =3.5)
    length of a periodic cycle = period (i.e.3.5pi - (-.5pi))
    horizontal shift = horizontal shift from the normal sin wave (i.e. amplitude/2-1)
    vertical shift= when y=horizontal shift , the least value of x
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Jul 2010
    Posts
    85

    just about

    definitions-periodic functions.docThis is what I got.
    see attached
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Senior Member BAdhi's Avatar
    Joined
    Oct 2010
    From
    Gampaha, Sri Lanka
    Posts
    252
    Thanks
    6
    sorry i was wrong

    since the main idea of finding the values of the variables is getting equation of the graph, one can deduce from the equation of the normal sine wave.

    for example,

    f(x) = sin(x) (amplitude = 1)

    to make the amplitude = a

    f1(x) = a.sin(x)

    then shift the wave up d number of units,

    f2(x) = a.sin(x) + d

    then move the wave left c number of units,

    f3(x) = a.sin(x+c) +d

    will it be correct this way?

    but what do you mean by period = \frac{2\pi}{b}
    Follow Math Help Forum on Facebook and Google+

  5. #5
    -1
    e^(i*pi)'s Avatar
    Joined
    Feb 2009
    From
    West Midlands, England
    Posts
    3,053
    Thanks
    1
    Quote Originally Posted by BAdhi View Post
    but what do you mean by period = \frac{2\pi}{b}
    I suspect (and only guess because I don't download and open files from the internet!) that it's related to f(x) = A\sin(Bx+C) + D where A, C and D are as defined in the post above.

    The period, is the "time/distance" it takes to reach the same point. For a standard sin or cos graph the period is 2\pi. As B is the amount the graph is compressed by this is going to change the period.

    It is divided by B (rather than multiplied) because the graph reaches the same point more quickly for large values of B.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. periodic functions
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: May 26th 2010, 08:31 PM
  2. Sum of periodic functions
    Posted in the Calculus Forum
    Replies: 6
    Last Post: September 24th 2009, 11:22 AM
  3. Periodic Functions
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: September 4th 2009, 07:43 AM
  4. Periodic Functions
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: February 8th 2009, 07:07 AM
  5. Periodic Functions
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: March 1st 2007, 05:58 PM

Search Tags


/mathhelpforum @mathhelpforum