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    f(x) = x2 + 4kx + (3 + 11k), where k is a constant.

    (a) Express f(x) in the form (x + p)^2 + q, where p and q are constants to be found in terms of k. (3 marks)


    I've tried completing the square of this but get to (x+2k)^2 - 4k^2+11k+3.
    Have I done this write and how would you get it into that form?
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    Correct.
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    (Original post by Bertybassett)
    f(x) = x2 + 4kx + (3 + 11k), where k is a constant.

    (a) Express f(x) in the form (x + p)^2 + q, where p and q are constants to be found in terms of k. (3 marks)


    I've tried completing the square of this but get to (x+2k)^2 - 4k^2+11k+3.
    Have I done this write and how would you get it into that form?
    That's fine and it is in the form they want.

    To be completely explicit, p = 2k and q = 3+11k - 4k^2 (I don't know if you would need to write something like this to get the marks. Personally I'd give them for what you wrote).
 
 
 
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