Question

1. He works hardest.
2. He works the hardest.
(Are both correct?)

3. She is most beautiful.
4. She is very beautiful.
5. She is the most beautiful.
(Does #3 mean #4 or #5?)

6. She is the most beautiful woman.
7. She is most beautiful woman.
8. She is a most beautiful woman.
9. She is a very beautiful woman.
(is #7 correct? Does #8 mean #9?)

Answer 1

1 is incomplete. Comparative and superlative forms are used for comparisons, but there's no hint of comparison in 1.

2 is OK. It implies that he works harder than all the other people in his group (whatever that may be).

3 and 4 mean the same thing, yes.

5 and 6 imply that "she" is more beautiful than all the others in her group (beauty contestants? female students? or what?).

7 is incorrect usage.

8 and 9 mean the same thing, yes.