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Math Help - comp of functions

  1. #1
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    comp of functions

    i cant seem to get the hold of it.

    Express the function in the form f g. (Use only elementary functions, but not the identity function, g(x) = x.)
    F(x) = cot(√x)
    f(x) = ?
    g(x) = ?


    f(x) = ?
    g(x) = ?
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  2. #2
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    Break each example down into two parts. What is going on in the first one? You have the cotangent of something and the square-root of something. That's all you need.
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  3. #3
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    Quote Originally Posted by Jameson View Post
    Break each example down into two parts. What is going on in the first one? You have the cotangent of something and the square-root of something. That's all you need.
    for the first one i tried
    F(x) = cot(√x)
    f(x) =
    1

    g(x) =
    2


    but they were both clearly wrong lol im so lost
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  4. #4
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    You're close. If f(x)=\cot(x) and g(x)=\sqrt{x}, then what's f(g(x))?

    I think of it in terms of inner and outer functions. The inner one should be g(x) if you are supposed to write f(g(x)). You are plugging g(x) into f(x).
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  5. #5
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    oh ok thank you that makes sense. i was switching the order
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  6. #6
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    for the second one i got:


    f(x) =
    1

    g(x) =
    2




    i dont understand what else can g(x) be??
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  7. #7
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    Talking

    What did you plug into the cube root, to get F(x)? That's what g(x) should be.
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