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    So the question is f(x) = 4/3+x

    g(x) = 9 - 2x^2

    Im asked to find fg(x)

    So when i put F into g i get

    4/9-2x^2 + 3 but, i need to get the plus 3 a common demonitor so i multipy it by 9 - 2x^2, but the answer is completley different to what i get where am i going wrong?
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    (Original post by SunDun111)
    So the question is f(x) = 4/3+x

    g(x) = 9 - 2x^2

    Im asked to find fg(x)

    So when i put F into g i get

    4/9-2x^2 + 3 but, i need to get the plus 3 a common demonitor so i multipy it by 9 - 2x^2, but the answer is completley different to what i get where am i going wrong?
    Don't understand, you're being totally ambiguous. Put up a picture.
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    (Original post by Zacken)
    Don't understand, you're being totally ambiguous. Put up a picture.
    Ok basically, the question is f(x) = 4 / 3 + x

    g(x) = 9 - 2x^2

    Im asked to find fg(x)

    The answer is 2 / 6 - x^2

    I just want to know how and why that is the answer, If u dont understand ill get a picture?
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    (Original post by SunDun111)
    Ok basically, the question is f(x) = 4 / 3 + x

    g(x) = 9 - 2x^2

    Im asked to find fg(x)

    The answer is 2 / 6 - x^2

    I just want to know how and why that is the answer, If u dont understand ill get a picture?
    f(g(x)) means replacing every time you see an x in 4/(3 + x) (please use brackets) you replace x with g(x).

    So f(g(x)) = \frac{4}{ 3 +x} = \frac{4}{3 + 9 - 2x^2}
 
 
 
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