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A - B is null.=> there are no elements in A - B.

=> there are no elements such that they are in A but not in B.

=> any element in A is in B.

=> A is a subset of B.

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Q: If A-B equals null set then prove A subset of B?
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What is the name of the eight grouping symbols?

The eight (8) grouping symbols related to set theory include the following: ∈ "is an element (member) of" ∉ "is not an element (member) of" ⊂ "is a proper subset of" ⊆ "is a subset of" ⊄ "is not a subset of" ∅ the empty set; a set with no elements ∩ intersection ∪ union


What is the largest number in a data set?

It's the maximum.Probably C, the continuum.The cardinality (count) of the infinite set of integers is Aleph-null. Then C = 2^(Aleph-null).


Prove that A contains N elements and the different subsets of A is equal to 2?

Assuming the question is: Prove that a set A which contains n elements has 2n different subsets.Proof by induction on n:Base case (n = 0): If A contains no elements then the only subset of A is the empty set. So A has 1 = 20 different subsets.Induction step (n > 0): We assume the induction hypothesis for all n smaller than some arbitrary number k (k > 0) and show that if the claim holds for sets containing k - 1 elements, then the claim also holds for a set containing k elements.Given a set A which contains k elements, let A = A' u {.} (where u denotes set union, and {.} is some arbitrary subset of A containing a single element no in A'). Then A' has k - 1 elements and it follows by the induction hypothesis that (1) A' has 2k-1 different subsets (which also are subsets of A). (2) For each of these subsets we can create a new set which is a subset of A, but not of A', by adding . to it, that is we obtain an additional 2k-1 subsets of A. (*)So by assuming the induction hypothesis (for all n < k) we have shown that a set A containing kelements has 2k-1 + 2k-1 = 2k different subsets. QED.(*): We see that the sets are clearly subsets of A, but have we covered all subsets of A? Yes. Assume we haven't and there is some subset S of A not covered by this method: if S contains ., then S \ {.} is a subset of A' and has been included in step (2); otherwise if . is not in S, then S is a subset of A' and has been included in step (1). So assuming there is a subset of A which is not described by this process leads to a contradiction.


How can you show that a set is a subset of another?

If you want to show that A is a subset of B, you need to show that every element of A belongs to B. In other words, show that every object of A is also an object of B.


This kind of proof required you to prove that all but one of a set of possible alternatives are false?

elementary proof

Related questions

What is the subset of null set?

The null set. Every set is a subset of itself and so the null set is a subset of the null set.


Is a null set in mathematics a subset of every set?

Yes the null set is a subset of every set.


What is universal subset?

The null set. It is a subset of every set.


Every subset of a null set is a null set?

yes


Does every set have a proper subset?

No. The null set cannot have a proper subset. For any other set, the null set will be a proper subset. There will also be other proper subsets.


Why a null set is subst of every set?

The definition of subset is ; Set A is a subset of set B if every member of A is a member of B. The null set is a subset of every set because every member of the null set is a member of every set. This is true because there are no members of the null set, so anything you say about them is vacuously true.


Is a null set is always a part of a universal set?

Yes. A null set is always a subset of any set. Also, any set is a subset of the [relevant] universal set.


Is null set a proper subset?

yes!


Is null set both a complement and subset of universal set?

Yes.


Why is it that the null set is a subset of all sets?

-- The null set is a set with no members. -- So it has no members that are absent from any other set.


Which set possesses only one proper subset?

A set with only one element in it. The only proper subset of such a set is the null set.


Why empty set or null set is subset of every set?

There is only one empty set, also known as the null set. It is the set having no members at all. It is a subset of every set, since it has no member that is not a member of any other set.