Answer:
[tex](f+g)(x)=\sqrt{3x+7}+\sqrt{3x-7}[/tex]
[tex]f(g(x))=x+1[/tex]
[tex]f(x)=x+9 \text{ and } g(x)=\frac{4}{x^2}[/tex]
[tex]f^{-1}(x)=\frax{x+2}{3}[/tex]
Let me know if you have any questions about any of my work.
Step-by-step explanation:
You are given the following:
[tex]f(x)=\sqrt{3x+7} \text{ and } g(x)=\sqrt{3x-7}[/tex]
and asked to find [tex](f+g)(x) \text{ which means } f(x)+g(x)[/tex].
If you add those because we are asked to find f(x)+g(x) you get:
[tex]\sqrt{3x+7}+\sqrt{3x-7}[/tex]
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You are given the following:
[tex]f(x)=x^2+3 \text{ and } g(x)=\sqrt{x-2}[/tex]
and asked to find [tex]f(g(x))[/tex].
[tex]f(g(x))[/tex]
[tex]f(\sqrt{x-2})[/tex] I replaced g(x) with sqrt(x-2) because that is what it equals.
Now this last thing means to replace old input in x^2+3 with new input sqrt(x-2) giving us:
[tex](\sqrt{x-2})^2+3[/tex]
[tex]x-2+3[/tex]
[tex]x+1[/tex]
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We are given [tex]y=\frac{4}{x^2}+9[/tex] and asked to find g(x) and f(x) such that y=f(g(x)).
We have choices so let's use the choices:
Choice A:
[tex]f(g(x))[/tex]
[tex]f(\frac{4}{x^2}){/tex] I replace g(x) with 4/x^2:
[tex]\frac{4}{x^2}+9[/tex] I replaced the old input x with new input 4/x^2.
This was actually the desired result.
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To find the inverse of f(x)=3x-2 or y=3x-2, your objective is to swap x and y and then remake y the subject.
y=3x-2
Swap x and y:
x=3y-2
Now solve for y.
Add 2 on both sides:
x+2=3y
Divide both sides by 3:
(x+2)/3=y
y=(x+2)/3
[tex]f^{-1}(x)=\frax{x+2}{3}[/tex]
