# Set Bulder Notaion? CONF

• Feb 27th 2010, 09:57 PM
mrsenim
Set Bulder Notaion? CONF
Hello,

I am confused what is the difference between the following statements.

(a)
{x | x > 0 And x < 10}
= {1,2,3,4,5,6,7,8,9}

(b)
{x | x > 0 OR x < 10}
??

It would be helpful if someone could please post tabular form for (b)

Thanks!
• Feb 27th 2010, 10:19 PM
Drexel28
Quote:

Originally Posted by mrsenim
Hello,

I am confused what is the difference between the following statements.

(a)
{x | x > 0 And x < 10}
= {1,2,3,4,5,6,7,8,9}

(b)
{x | x > 0 OR x < 10}
??

It would be helpful if someone could please post tabular form for (b)

Thanks!

Well, there is a huge difference. Let's assume the ambient set is $\displaystyle \mathbb{Z}$ then $\displaystyle -1\notin A,-1\in B$
• Feb 28th 2010, 02:34 AM
HallsofIvy
Quote:

Originally Posted by mrsenim
Hello,

I am confused what is the difference between the following statements.

(a)
{x | x > 0 And x < 10}
= {1,2,3,4,5,6,7,8,9}

(b)
{x | x > 0 OR x < 10}
??

It would be helpful if someone could please post tabular form for (b)

Thanks!

Every number is either less than 10 or greater than 0!