SOLUTION: Given that g(x)=4/x , x is not equal to 0 and fg(x)=2x+3 find the function f.
f(4/x)=2x+3 how do i find f(x)???? Help
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-> SOLUTION: Given that g(x)=4/x , x is not equal to 0 and fg(x)=2x+3 find the function f.
f(4/x)=2x+3 how do i find f(x)???? Help
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Question 1073536: Given that g(x)=4/x , x is not equal to 0 and fg(x)=2x+3 find the function f.
f(4/x)=2x+3 how do i find f(x)???? Help Answer by ikleyn(52788) (Show Source):
---------------- Comment from student: composition.
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My responce. OK, composition.
1. First of all, it means that your original formulation in the post was wrong.
The correct writing is fog(x)=2x+3.
The composition is always denoted as fog.
2. Then you can write fog(x) = f(g(x)) = = 2x + 3.
Replace here by other variable, for example, t.
You will get f(t) = 2x + 3.
But since t = , you have x = , therefore
f(t) = = .
Now you can replace t in both sides by x (it is simply another symbol for the variable), and you will get f(x) = .
