Interval Notation: Clear Explanation

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Can anyone please give a succinct and clear description on this? I'm a little confused...
 
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(a, b) means "all numbers strictly between a and b". It can also be written as [itex]\{x| a< x< b\}[/itex].

[a, b) means "all numbers strictly between a and b and the number a. It can also be written as [itex]\{x| a\le x< b\}[/itex].

(a, b) means "all numbers strictly between a and b and the number b. It can also be written as [itex]\{ x| a< x\le b\}[/itex].

[a, b] means "all numbers strictlhy between a and b and both the number a and the number b. It can also be written as [itex]\{x| a\le x\le b\}[/itex].

In short, all of these contain the interval between a and b. "[" and "]" mean "include this end point". "(" and ")" mean "do not include this point".
 
HallsofIvy said:
(a, b) means "all numbers strictly between a and b". It can also be written as [itex]\{x| a< x< b\}[/itex].

[a, b) means "all numbers strictly between a and b and the number a. It can also be written as [itex]\{x| a\le x< b\}[/itex].

(a, b) means "all numbers strictly between a and b and the number b. It can also be written as [itex]\{ x| a< x\le b\}[/itex].

[a, b] means "all numbers strictlhy between a and b and both the number a and the number b. It can also be written as [itex]\{x| a\le x\le b\}[/itex].

In short, all of these contain the interval between a and b. "[" and "]" mean "include this end point". "(" and ")" mean "do not include this point".

Third, HOI certainly means (a,b], just in case this is not caught.