Difference between revisions of "Element"
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=== Elements Within Elements === | === Elements Within Elements === | ||
| − | Elements can also be [[set]]s. For example, <math>B = \{1,\,2,\,\{3,\,4\}\}</math>. The elements of <math>B</math> are not 1, 2, 3, and 4. Actually, there are only three elements of <math>B</math>: 1, 2, and the [[set]] <math>\{3,\,4\}</math>. | + | Elements can also be [[set]]s. For example, <math>B = \{1,\,2,\,\{3,\,4\}\}</math>. The elements of <math>B</math> are not 1, 2, 3, and 4. Actually, there are only three elements of <math>B</math>: <math>1</math>, <math>2</math>, and the [[set]] <math>\{3,\,4\}</math>. |
| + | |||
| + | === Cardinality === | ||
| + | |||
| + | The amount of elements in a [[set]] is known as [[cardinality]]. If <math>C=\{1,\,2,\,3\}</math>, then the cardinality of <math>C</math> is <math>3</math>. Informally, cardinality is the size of a [[set]]. | ||
==See Also== | ==See Also== | ||
* [[Set]] | * [[Set]] | ||
Revision as of 22:45, 30 October 2006
This article is a stub. Help us out by expanding it.
An element, also called a member, is an object contained within a set or class.
means set 
contains the elements 1, 2, 3 and 4.
To show that an element is contained within a set, the 
symbol is used. If 
, then 
.
The opposite of this would be 
, which means the element is not contained within the set.
Elements Within Elements
Elements can also be sets. For example, 
. The elements of 
are not 1, 2, 3, and 4. Actually, there are only three elements of : 
, 
, and the set 
.
Cardinality
The amount of elements in a set is known as cardinality. If 
, then the cardinality of 
is 
. Informally, cardinality is the size of a set.
