How do you find out cardinality? - Answers

cardinality is the number of element in a set :) * * * * * The question did not ask what cardinality was but how to find it! For a simple set with a finite number of elements it is possible to count the number of distinct elements - even though it may be time consuming. For other finite sets, such as symmetry groups, it is not always easy to identify distinct elements before counting how many there are. However, there are theoretical methods that will help in such cases. The cardinality of an infinite group is Aleph-Null if it there is a 1-to-1 mapping with the set of integers. The cardinality is Aleph-One if the mapping is with the real numbers. If you go beyond that, you will have studied a lot more about cardinality and will not need to ask such a question!