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Math Help - Finding the cubic function rule

  1. #1
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    Finding the cubic function rule

    Hi i would like some help on finding the expression for the following cubic curve:



    hope someone can help

    P.S
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  2. #2
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    Quote Originally Posted by Paymemoney View Post
    Hi i would like some help on finding the expression for the following cubic curve:



    hope someone can help

    P.S
    1. The general equation of a cubic function is:

    f(x)=ax^3+bx^2+cx+d

    2. Since the graph passes through the origin you already know that d = 0.

    3. Plug in the coordinates of the given points into the genral equation. You'll get a system of 3 equations:

    \left|\begin{array}{l}3 = 8a+4b+2c \\\frac34 = a+b+c \\ -3=-8a+4b-2c \end{array}\right.

    4. Solve for (a, b, c)
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  3. #3
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    Thanks i think i know how to work it out now
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