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    I've been given two functions
    f(X) = 18x+3
    g(x)= 28-d

    how do I find the value of d?
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    (Original post by Kmachakanja1)
    I've been given two functions
    f(X) = 18x+3
    g(x)= 28-d

    how do I find the value of d?
    Where is the x in g(x)? Was that a typo?

    You could find d if you where given fg(x) or gf(x).
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    typo
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    F(x)= 18x+3
    g(x)= 28x-d

    how do I find the value of d?
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    (Original post by Kmachakanja1)
    typo
    What was g(x) or can you send a photo of the question?
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    (Original post by Kmachakanja1)
    F(x)= 18x+3
    g(x)= 28x-d

    how do I find the value of d?
    Do you have the value of g(x), fg(x) or gf(x)?
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    this is the question :

    two functions are defined by

    f(X)= 18x 3.
    g(X) = 28x-d

    where d is an unknown number. it is known that
    f^-1 g^-1 (x) = g^-1 f^-1(x)

    Find the value of d?
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    (Original post by Kmachakanja1)
    this is the question :

    two functions are defined by

    f(X)= 18x 3.
    g(X) = 28x-d

    where d is an unknown number. it is known that
    f^-1 g^-1 (x) = g^-1 f^-1(x)

    Find the value of d?
    Spoiler:
    Show


    f^-1(x) = (x-3)/18
    g^-1(x) = (x+d)/28

    To find d I used a graphing website and found d = -(81/17). I double checked by finding f^-1g^-1(x) = g^-1f^-1(x).
    It is probably wrong but it's the best I could do.



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    (Original post by Kmachakanja1)
    this is the question :

    two functions are defined by

    f(X)= 18x 3.
    g(X) = 28x-d

    where d is an unknown number. it is known that
    f^-1 g^-1 (x) = g^-1 f^-1(x)

    Find the value of d?
    (Original post by Kmachakanja1)
    this is the question :

    two functions are defined by

    f(X)= 18x 3.
    g(X) = 28x-d

    where d is an unknown number. it is known that
    f^-1 g^-1 (x) = g^-1 f^-1(x)

    Find the value of d?
    When you put f^-1 g^-1 (x) is that a product or composition of functions?
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    composition of functions
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    thanks loci Pi
    that was the correct answer
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    (Original post by Kmachakanja1)
    thanks loci Pi
    that was the correct answer
    No problem
    Just out of interest, was that question for GCSE or A levels?
 
 
 
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