Composition of Functions (check me)

AI Thread Summary
The discussion revolves around finding the compositions of two functions, f(x) = x^2 + 2 and g(x) = √x. The user calculates f ∘ g as f(g(x)) = x + 2, and g ∘ f as g(f(x)) = √(x^2 + 2). However, it is pointed out that g(x) is only defined for x in the range [0, ∞), which affects the validity of the compositions. The user seeks confirmation on the correctness of their solutions. The conversation emphasizes the importance of considering the domain of the functions when performing compositions.
Lynne
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Hi,

Homework Statement


Given:f(x)=x^2+2 and g (x)=\sqrt{x}

Find: f \circ g and g \circ f

2. The attempt at a solution
f \circ g =f(g(x))=x+2, where x\in (-\infty ; +\infty)

g \circ f =g(f(x))=\sqrt{x^2+2} where x\in (-\infty ;+ \infty)

I haven't done this for a while, and I'm not sure about my solution. Is it correct?
 
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Almost. Except g(x) is only defined for x in [0,infinity).
 

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