I pretty confuse about the domain and range I think is (-infinity, -3) U (-3, +infinity). for the domain and I don't know how to calculate the range. please someone help me

View attachment 39725 I pretty confuse about the domain and range I think is (-infinity, -3) U (-3, +infinity). for the domain and I don't know how to calculate the range. please someone help me

The domain is \(\displaystyle (-\infty,-3)\cup [3,\infty)\) now that is different from what you posted is only one symbol. What is it and why?
Hint: \(\displaystyle \circ\text{ as oppose to } \bullet\)
You post the range.