Answer:
-3
Step-by-step explanation:
Given, f(x)=-4log2(x+3)-6
So, for domain of f(x) ,we have to find the domain of log2(x+3) as all other things are just numbers which do not affect the domain.
For domain of f(x), 2(x+3) > 0
Thus, x + 3 > 0
x > -3.
So, all real numbers greater than -3 are in the domain of f(x).