Answer:
x = 8
Step-by-step explanation:
f(x) = [tex]\sqrt{3x}[/tex]
g(x) = [tex]\frac{1}{x+3}[/tex]
(f o g)(x) = f[g(x)]
= [tex]\sqrt{\frac{3}{x+3} }[/tex]
This function is defined for (x + 3) > 0
(x + 3) - 3 > 0 - 3
x > -3
From the given options x = 8 is the only solution which is greater than -3.
Therefore, x - 8 is in the domain of the given function.