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functions question... watch

1. 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...

Thanks
2. 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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