The domain of this function is the set of all real numbers.
It is so, because for any x the value of the expression
under the square root is non-negative.
Solved.
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comment from student: Cool but is this solved algebraically? Do we set 4^(x + 4) to be greater than or equal to 0?
My response: We do not set to be greater than or equal to zero,
because this function is just itself greater than zero, even without any special care
from our side, simply due to the nature of things.
It is the pre-requisite, which you should know when you get this assignment.
If you don't know this fact, then it is a warning signal that something is wrong
with the sequence of steps in your mathematical education.
