Question

Domain and range, how would i write it for this?

There are open circles and dots, and they are confusing me.

Answer 1

• domain: [1, 2) ∪ (2, 4) ∪ (4, 6]
• range: [1, 3) ∪ (3, 5) ∪ (5, 6]

Explanation:

The open circles identify points where the function is not defined. They are excluded from both the domain and the range.

The domain is the horizontal extent of the function. This function is defined on the interval [1, 6], except at points x=2 and x=4, so those values need to be excluded from the domain.

The range is the vertical extent of the function. This function is defined between y=1 and y=6, excluding values y=3 and y=5. Those y-values will be excluded from the range.

In the interval notation used above, the curved bracket means the value is excluded. All values up (or down) to that are included, but that one is not. The square bracket means the end value is included in the interval.