It is a universal set
That's not true. All sets have zero or more elements. You can have a set with zero elements - the "empty set".
Yes.
Equivalent sets are sets that have the same cardinality. For finite sets it means that they have the same number of distinct elements.For infinite sets, though, things get a bit complicated. Then it is possible for a set to be equivalent to a proper subset of itself: for example, the set of all integers is equivalent to the set of all even integers. What is required is a one-to-one mapping, f(x) = 2x, from the first set to the second.
The set of elements that are elements of the two (or more) given sets is called the intersection of the sets.
Because non set establishes the value of "0". Imagine that it is not empty set, but that it is an invisible value that is always located within a set no matter what the values inside brackets are.
the union of two convex sets need not be a convex set.
A non-element can be a set that does not contain any elements, known as the empty set or null set, denoted by {}. It is not considered an element in itself but rather a subset of all sets.
It is a universal set
The empty set is a subset of all sets. No other sets have this property.
Yes all sets have subsets.Even the null set.
There is no such thing as a "set of all sets". To be more precise, the idea of a "set of all sets" leads to contradictions; therefore this term is avoided in set theory. Check the Wikipedia article on "Universal set" for more details.
That is called the UNION of the two sets.
The union of a collection of sets is defined as the set of all distinct elements that are in the collection. This includes the specific case where the collection consists of two sets.
All non-zero sets of integers have at least one common factor. It's 1.
An example is given here: http://en.wikipedia.org/wiki/Non-Borel_set Any set that is easy to think of will be a Borel set, so an example of a non-Borel set will be complicated. Another approach: All Borel sets are Lebesgue measurable. The axiom of choice can be used to give an example of a non-measurable set, and this set will also be a non-Borel set. See http://en.wikipedia.org/wiki/Non-measurable_set = =
That's not true. All sets have zero or more elements. You can have a set with zero elements - the "empty set".