Interval notation uses parenthesis ( or ) for points that are not included in the function (open circle) and brackets [ or ] for points that are included in the function (filled in circle).
Remember that the domain for a function is the range of x-values in a function.
Interval notation includes the numbers at the each end of a continuous function. For function F, the leftmost x-value is 0. The rightmost x-value is 8. Both points at x = 0 and x = 8 are included in the function (filled in circles), so you would use the brackets. The entire function is continuous between those two points.
That means the interval notation for the domain of F is:
[0, 8]
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Answer: [0, 8]
