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    The curve C with equation y=f(x) is such that
    \frac{dy}{dx} = 3x^2 + kx, where k is a constant.
    1. Find the value of k.


    so far, i have integrated to get x^3 + \frac{k}{2}x squared + c.
    What do i need to do to find the value of k after this?
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    (Original post by Chelsea12345)
    The curve C with equation y=f(x) is such that
    \frac{dy}{dx} = 3x^2 + kx, where k is a constant.
    1. Find the value of k.


    so far, i have integrated to get x^3 + \frac{k}{2}x squared + c.
    What do i need to do to find the value of k after this?
    You need at least 2 points through which the curve passes through, or any other addition information.
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    (Original post by RDKGames)
    You need at least 2 points through which the curve passes through, or any other addition information.
    C passes through the points(1,6) and (2,1)
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    (Original post by Chelsea12345)
    C passes through the points(1,6) and (2,1)
    Plug those two into y=f(x) and solve the simultaneous equations in c and k
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    K=-8
    C=9
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    (Original post by Mr Moon Man)
    K=-8
    C=9
    Please don't provide full solutions. The Forum Rules specifically prohibit this. Read the Guide To Posting at the top of the Maths Forum.
 
 
 
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