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Calculus Problem

  1. Nov 14, 2004 #1
    f(x) = (ax+b)/(x-c) has the following properties

    i) the graph of f is symmetric with respect to the y-axis
    ii) lim x->2^+ f(x) = + infinite
    iii) f^prime (1) = -2

    a) Determine the values of a, b and c.

    i think c = 2

    derivative of f(x) = (-ca - b)/(x-c)^2

    so f^prime(1) = -2

    -ca-b = (1-c)^2 * -2

    if c = 2 then b = -2a + 2

    I'm stuck from here. I have no idea how to do this. I tried using this equation
    (ax+b)/(x-2) = (-ax + b)/(-x-2)

    since symmetric over y axis and i plugged in b, but it turned out to be useless. Please help. thanks
  2. jcsd
  3. Nov 15, 2004 #2


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    Homework Helper

    Check the question again, and the 3 conditions. As the question is stated, I don't think there's any solution for a,b and c.
  4. Nov 15, 2004 #3

    James R

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    I agree. There seems to be no solution.
  5. Nov 15, 2004 #4
    thanks for your time. This was all my teacher's fault. He didn't give us the correct question. It was (ax+b)/(x^2-c). Wow what a waste of time. I solved it anyways though, and again thanks for all your time.
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