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A strange function .

  1. Dec 1, 2006 #1
    A strange function.....

    Last night I was faced with a strange function & I couldn't figure out the eqation of the function hence I thought I can get some help from the math experts over here...

    The function passes through these cordinates:

    (3,1) (4,1) (5,2) (6,2) (7,3) (8,3) (9,4) (10,4) ..............
    it's logicallt very simple to predict it's next terms but I still couldn't find the equation....

    I'd be really really glad if someone would help me figure this out...
  2. jcsd
  3. Dec 1, 2006 #2

    add two functions. a diagonal ascending one like y = x/2, and an oscilating one like sin. fiddle with coefficients to get it right
  4. Dec 1, 2006 #3


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    Homework Helper

    You may want to investigate this: http://mathworld.wolfram.com/LagrangeInterpolatingPolynomial.html" [Broken].
    Last edited by a moderator: May 2, 2017
  5. Dec 1, 2006 #4
    trouble with that is it covers a finite number of points. the sequence in the post is infinite

    i reckon (2x - 3 - Cos[Pi x])/4 will do it. Cos taking radian arguments. silly errors aside
    Last edited by a moderator: May 2, 2017
  6. Dec 1, 2006 #5
    Try using the floor function:

    [tex]\left(x, \lfloor \frac{1}{2}\left( x-1 \right) \rfloor \right)[/tex]

    That is the function might look like this:

    [tex]f: [3,\infty) \rightarrow \Re; x \mapsto \lfloor \frac{1}{2}\left(x-1\right) \rfloor [/tex]
    Last edited: Dec 1, 2006
  7. Dec 1, 2006 #6
    Thanks from everybody who posted.
    The problem is solved & you were all a great help
    Once again Thankyou...
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