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Homework Help: Inflection Points and Local Minimums

  1. May 3, 2010 #1
    1. Use the following equations to fill in the missing numbers. The correct addition and subtraction signs have already been entered.

    f(x) = ax4 + bx3 - cx2 - dx - e

    Find values of a,b,c,d, and e so that the function has inflection points at ((v3)/3, -7.5752) and (-(v3)/3, -.647009) and has a local minimum at (1.26255, -11.8696).

    f(x) = qx4 - rx3 - sx2 +tx + u

    Find values of q, r, s, t, and u so that the function has local minimums at (-.398238, -.457621) and (1.20556, -3.46602) also so the function has a local maximum at (.130182, .069458).

    2. See above

    3. ?

    I never took calculus. Need assistance in solving these problems to solve a puzzle. I need to know what the values are for a, b, c, d, e and q, r, s, t, u.

    Thank you.
  2. jcsd
  3. May 3, 2010 #2


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    Gold Member

    Were you really given those decimals or have you rounded something off?

    Try q = 4, r = 5, s = 3, t = 1, u = 0
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