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Math Help - Find the domain of the composite function fxg

  1. #1
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    Find the domain of the composite function fxg

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

    i don't get how this works..
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  2. #2
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    Quote Originally Posted by FinalFantasy9291 View Post
    f(x)=3/x-1;g(x)=2/x

    i don't get how this works..
    Is f(x)= \frac{3}{x-1}

    or \frac{3}{x}-1 ???
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  3. #3
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    the first one
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  4. #4
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    f\circ g(x)= \frac{3}{\frac{2}{x}-1}=\frac{3x}{2}-3

    So it can accept any real or complex argument
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  5. #5
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    Quote Originally Posted by Greengoblin View Post
    f\circ g(x)= \frac{3}{\frac{2}{x}-1}=\frac{3x}{2}-3

    So it can accept any real or complex argument
    Correction: \frac{3}{\frac{2}{x}-1}= \frac{3x}{2 - x}.
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  6. #6
    Member Greengoblin's Avatar
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    Ooops my mistake, so the domain is \{x\in\mathbb{R}:x\ne 2\} that certainly makes more sense.
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