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C3 help number two.

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    As I predicted, I'm well on the way to asking a whole heap of questions about C3. This time I'm having difficult with functions:

    f(x)=x-2
    g(x)=5/(x+2)

    h=fg

    so
    a) find h(x)
    b) find h^-1

    I got h(x) to be 5/(x+2) -2 and x can't equal -2, however I then couldn't do part b) as I kept ending up with either an xy or an x/y when trying to get y by itself.

    Thanks in advance
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    (y+2)(x+2)=5

    x+2=5/(y+2)

    ....
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    (Original post by mathz)
    (y+2)(x+2)=5

    x+2=5/(y+2)

    ....
    And with hindsight, it's actually really obvious...:rolleyes:

    Thanks though, fancy sitting the exam with me and pointing out all the things I miss?

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Updated: September 23, 2012
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