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Homework Help: Differentiable function

  1. Dec 13, 2005 #1
    :smile: For all real numbers x, f is a differentiable function such that f(-x) = f(x). Let f(p) = 1 and f'(p) = 5 for some p>0.

    a) Find f'(-p).
    b)FInd f'(0).
    c)If ß1 and ß2 are lines tangent to the graph of f at (-p,1) and (p,1) respectibely, and if ß1 and ß2 intersect at point Q, find the x and y coordinates of Q in terms of p.

    SO basically the week we did this stuff I was out with pneumonia for 6 days. Sucks, but know I am stuck with this assignment sheet. I pretty much don't know where to begin on this. Any help would be greatly appreciated.
  2. jcsd
  3. Dec 14, 2005 #2


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    Homework Helper
    Gold Member

    There was a very similiar problem in another forum, and you might be the same person. :confused:

    Go check it out, I think it's in General Math. Completely identical.
  4. Dec 14, 2005 #3
    You might consider:

    Since f(-x) = f(x), this makes f an even function, i.e., symmetric about the y axis..

    symmetry should say something about the value of the slope at equal distances from x=0.
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