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    f(x) = |x-2|-3
    g(x) = x^2 - 4x + 11

    How do you find the composite function gf(x)?
    I can do these normally, but don't really know how to do it when modulus functions are involved. I asked my teacher but he's useless, he didn't know.

    Any help would be much appreciated

    (oh, and if it makes a difference, the actual question is 'Find gf(-1)' I assume that you have to find out what the composite function actually is and then sub in -1, but perhaps this is not the case?)

    It's only worth 2 marks so shouldn't be too hard, I just don't know how to do it...


    I would find f(-1) which gives 0, then substitute x=0 into g(x), giving 11.
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Updated: October 13, 2009

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