# Cardinality of a Set

• January 27th 2009, 03:18 PM
nikie1o2
Cardinality of a Set
Im looking for the cardinality of a Set where X is an element of the Real Numbers such that lxl = -1..... what's this mean ?!
• January 27th 2009, 03:21 PM
Plato
HINT: There is no real number such that $|x|=-1$
• January 27th 2009, 03:25 PM
nikie1o2
Quote:

Originally Posted by Plato
HINT: There is no real number such that $|x|=-1$

So, Would it just be the empty Set ?
• January 27th 2009, 03:33 PM
Plato
Well, YES.