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Math Help - Inverse of a function help!

  1. #1
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    Inverse of a function help!

    So I am asked to find the inverse of the functon: f(x) = (4x-1)/(2x+3)

    so y=f(x) and interchange x with y...

    So I start by multiplying both sides by 2y+3 to get x(2y+3) = 4y-1

    Now I am not really sure what to do. I tried making it 2y+3-4y = -1/x

    then -2y = -1/x -3

    and -y = (-1/x -3)/2

    But I think this is still the wrong answer. Can anyone lead me onto the right track? Thanks!
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  2. #2
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    Quote Originally Posted by Landyach View Post
    So I am asked to find the inverse of the functon: f(x) = (4x-1)/(2x+3)
    x = \frac{4y-1}{2y+3}

    2xy+3x = 4y-1

    2xy - 4y = -3x -1

    y(2x - 4) = -(3x+1)

    y = -\frac{3x+1}{2x-4}
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  3. #3
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    Quote Originally Posted by skeeter View Post
    x = \frac{4y-1}{2y+3}

    2xy+3x = 4y-1

    2xy - 4y = -3x -1

    y(2x - 4) = -(3x+1)

    y = -\frac{3x+1}{2x-4}
    thanks so much!
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