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Pls help pls helppp i will giving breanlist

Let f (x) = 7+3 and g(x) = Vx+5. What is the domain of (fºg)(x)?

Pls help pls helppp i will giving breanlist Let f (x) = 7+3 and g(x) = Vx+5. What-example-1
User Kds
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1 Answer

9 votes

Answer:

[-5, 4) ∪ (4, ∞)

Explanation:

Given functions:


f(x)=(1)/(x-3)


g(x)=√(x+5)

Composite function:


\begin{aligned}(f\:o\:g)(x)&=f[g(x)]\\ & =(1)/(√(x+5)-3) \end{aligned}

Domain: input values (x-values)

For
(f\:o\:g)(x) to be defined:


x+5\geq 0 \implies x\geq -5


√(x+5)\\eq 3 \implies x\\eq 4

Therefore,
-5\leq x < 4 and
x > 4

⇒ [-5, 4) ∪ (4, ∞)

User Elliot Cameron
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