Answer:
Domain = [0,∞)
Explanation:
The given function is

where, y is the price of x in game power boost.
Domain is the set of input values or x-values.
It means the reasonable domain of the given function is the possible number of games. So, domain of the given function can't be negative.
Set builder form of domain is

Interval notation of domain is

Therefore, the reasonable domain for the given function is [0,∞).