- #1

- 21

- 0

What if closed intervals are half closed as following (-inf, f]. 'f' being rational.

- Thread starter gradnu
- Start date

- #1

- 21

- 0

What if closed intervals are half closed as following (-inf, f]. 'f' being rational.

- #2

CompuChip

Science Advisor

Homework Helper

- 4,302

- 47

What about something like

[tex](a, b)^C = (-\infty, a] \cup [b, \infty) [/tex]

[tex](a, b)^C = (-\infty, a] \cup [b, \infty) [/tex]

- #3

- 2

- 0

[tex](a,b) = [a+1,b-1] \cup [a-0.5,b+0.5] \cup\dots[/tex]

- #4

- 21

- 0

Thanks.

- #5

CompuChip

Science Advisor

Homework Helper

- 4,302

- 47

- #6

- 1,074

- 1

Intersection, not union here. Assuming the first one on the right side was supposed to be [a-1,b+1] then this union is equal to [a-1,b+1].

[tex](a,b) = [a+1,b-1] \cup [a-0.5,b+0.5] \cup\dots[/tex]

- #7

- 1,074

- 1

It should be closed, as it is the complement of an open set (a, inf) which is open.

- Last Post

- Replies
- 2

- Views
- 16K

- Last Post

- Replies
- 2

- Views
- 4K

- Last Post

- Replies
- 2

- Views
- 6K

- Last Post

- Replies
- 1

- Views
- 4K

- Last Post

- Replies
- 8

- Views
- 10K

- Last Post

- Replies
- 2

- Views
- 3K

- Last Post

- Replies
- 25

- Views
- 4K

- Last Post

- Replies
- 2

- Views
- 1K

- Last Post

- Replies
- 4

- Views
- 2K

- Last Post

- Replies
- 1

- Views
- 1K