I think (a) is \(1 \le x <2\),
(b) is \(3 \le x <4\)
and (c) is \(5 \le x <6,\) but I'm not sure.
Also I still need help on (d).
I also think this question is too easy and I'm doing something wrong...
Edit: Yes all my thoughts for the answers are all wrong since I didn't see the extra x multiplying the first floor function. I'll try to work on (a), (b) and (c) but will probably still need help.
Edit Edit: After furthur examination my answers for a-c might actually be right.
Edit Edit Edit: I got answers for a-c (a was right and b-c were wrong but I got the right answers) I'm working on (d)
Edit Edit Edit Edit: I got the question no help needed