# math: real numbers

posted by
**sara** on
.

The statement below is false. Correct it by changing two symbols.

"The interval (a,b) contains its infimum and its supremum."

I'll give you a hint.

The interval (a, b) is an open interval. What you need is a closed interval.

Parentheses are used for open intervals.

What symbol is used for closed intervals?

I hope this will help.