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Thread: High School Calculus Help [+Rep]

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    High School Calculus Help [+Rep]

    F(x) = 2kx^3 + 3x^2 + px - 3 has a local minimum at x=-1 and a point of inflection at x = 1. Determine the values of K and P.

    ^ is the power to x number

    Obviously I need first and second derivatives

    F'(X) = 6kx^2 + 6x + p
    F''(x) = 12kx + 6




    But i am not sure where to move onto next. Step by step would be nice but I am sure I could figure it out if you posted any sort of help. +Rep to people who help me solve for tomorrow.




    ----
    SOLVED
    Solution

    F"(x) = 12kx + 6
    F"(1) = 12k(1) + 6
    K = 1/2


    F'(x) = 6kx^2 + 6x + p
    F'(-1) = 6K(-1)^2 + 6(-1) + p
    0= 6(.5)(-1) - 6 + p
    0= 6(-.5) - 6 + p
    0 = -3 -6 + p
    9=p



    A lot easier than I thought.
    Last edited by Hurricane; 04-03-2016 at 08:05 PM.
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