I'm new to this, so why is {xlx is a number less than 3 and greater than 5} an empty set?

Question

also, {xlx is a number less than 3 or greater than 5}? does it have something to do with the word "or" "and"

Answer 1

The and makes a big difference.  There is no number that is both less than 3 AND greater than 5.  That's why it's an empty set.

If you change it to "or", there are lots of answers.  Any number that is less than 3 OR greater than 5 works.

_/

Answer 2

{xlx is a number less than 3 and greater than 5}

means all the x, where x is number < 3 and at the same time > 5.

The "and" means "at the same time".

Since there is no number like this, the set is empty.

Answer 3

there are no numbers that are both less than 3 and greater than 5

if it was numbers that are less than 3 or greater than 5, it would be all number excluding 3 4 and 5