Domain of a function
We have the function M(n):
M( n ) = 9 · n
which describes the amount of money the theater takes.
Since the domain of a function refers to the values n can take and n is the number of costumers
In this particular case we do not have a restriction of the number of costumers. Then n can take the following values:
n = 0, 1 , 2, 3, ...
Domain: all non- negative integers
If the maximum capacity of the theater is 100 costumers then
n = 0, 1, 2, 3, ..., 100
Therefore its domain would correspond to
Domain: all non- negative integers less than or equal to 100