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Math Help - Functions / Composition

  1. #1
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    Functions / Composition

    alright, the problem I need help on is showing that two functions are inverses of each other using composition.

    f(x) = x + 3 / x - 2 and g(x) = 2x - 3 / x - 1

    I've gotten to this point below and don't know where to go from there

    f(g(x)) = (2x - 3 / x - 1) + 3 / (2x - 3 / x - 1) - 2

    any help would be great, thanks

    -Laconian
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  2. #2
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    alright, the problem I need help on is showing that two functions are inverses of each other using composition.

    f(x) = (x + 3)/(x - 2) and g(x) = (2x - 3)/(x - 1)

    next time, use parentheses for clarity
    re-check f(x) and g(x) ... they are not inverses.

    f(3) = 6

    but

    g(6) \neq 3
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  3. #3
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    Well the entire question is "Use composition to show that f(x) and g(x) are inverse of each other. What I showed before is correct.

    Is the question also asking to show that they are not inverses if their not.

    -Laconian
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