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I need help on this question pls answer :(

I need help on this question pls answer :(-example-1
User Cgross
by
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1 Answer

3 votes

Answer:

Option 3

Explanation:

Given functions are,

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

g(x) =
√(x+5)

Therefore, composite function (f o g) will be,

(f o g)(x) = f[g(x)]

=
(1)/(√(x+5) -3)

This function will be defined for,

Denominator > 0


√(x+5)-3>0


√(x+5) >3


(x+5)>3^2


x+5>9


x>9-5


x>4

And
x+5\geq 0


x\geq -5

Therefore, domain of the composite function will be,

[-5, 4) ∪ (4, ∞)

Option 3 will be the answer.

User Mvbl Fst
by
5.0k points