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1. 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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2. (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).
3. typo
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4. F(x)= 18x+3
g(x)= 28x-d

how do I find the value of d?
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5. (Original post by Kmachakanja1)
typo
What was g(x) or can you send a photo of the question?
6. (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)?
7. 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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8. (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.

9. (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?
10. composition of functions
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11. thanks loci Pi
that was the correct answer
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12. (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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