Margot Hudson
December 10, 2015
Q. Reasoning and Mathematical Skills

Blog 4: Be the Professor

I'm going to explain the topic of Sets.
A set is a collection of something (objects, numbers, etc.).
Elements are members of the set.


There are two types of sets: Well-defined and subjective

A well-defined set is a set for which there is a way of determining whether or not an item is an element of the set; subjective means that there is no way to determine whether or not an item is an element of the set.

There are also different notations for writing out sets.
One of those notations is Set Builder Notation which determines whether or not an object is an element of the set rather than actual elements.
Ex) B= {Boy | the boy who cried wolf}

A universal set is the set of all elements.
Ex) A= the set of all musical artists that are female
In this case "A" is the universal set.
A subset is for every element in set A the subset follows that element.
A cardinal number (cardinality) is the number of all elements in the set
-denoted n(A)
An empty set is always the subset of the universal set