the value y = 0 does not belong to the range, that is why we need to use parenthesis next to the range.
When we write in interval notation, the parenthesis are used to denote that the "ends" of the interval don't belong to the interval.
This means that in (a, b).
a and b don't belong to that interval.
While if instead we wrote [a, b]
In that case, a and b belong.
For the case of the exponential function:
y = a^x
As x tends to really large negative values, the value of y will tend to zero asymptotically. This means that y is really close to zero, but it is never equal to zero.
Then the value y = 0 does not belong to the range, that is why we need to use parenthesis next to the range.
If you want to learn more about interval notation:
https://brainly.com/question/4307772
#SPJ1
