Posted by **Roger** on Thursday, June 9, 2011 at 11:59am.

3 questions if you can help me.

1. Calculate the number of subsets and the number of proper subsets for the set.

{x|x is a day of the week}

2. Let U = {q, r, s, t, u, v, w, x, y, z}

A = {q, s, u, w, y}

B = {q, s, y, z}

C = {v, w, x, y, z}. List the elements in the set.

(A n B)u(A n C)

- Math -
**MathMate**, Thursday, June 9, 2011 at 12:21pm
1. the answer is the "power set", i.e. the set of all possible subsets of the given set. The cardinality of the power set of A is equal to 2^(|A|).

For example:

A={1,2}

power set of A ={∅,1,2,{1,2}}

with 4 elements = 2^2.

so if {x|x is a day of the week},

then

n=|x|=7, and the power set of x has 2^7 members.

The number of proper subset is 1 less than 2^n.

2.

A∩B={q,s,y}

A∩C={w,y}

Can you find (A∩B)∪(A∩C)?

## Answer This Question

## Related Questions

- Math - 3 questions if you can help me. 1. Calculate the number of subsets and ...
- algebra - How many sets are subsets of set B? List the subsets of set B. Which ...
- Math - How many subsets of a set with 100 elements have more than one element? ...
- math - Given a set with n elements has 2^n subsets.Find the number of subsets ...
- College Mathematics - The number of proper subsets of set A are? When A= {1,3,5,...
- math - How are the ideas of subsets and proper subsets used in counting to ...
- Modern (Abstract) Algebra - Let f:A->B, where A and B are nonempty Prove that...
- Modern (Abstract) Algebra - Let f:A->B, where A and B are nonempty Prove that...
- Math - To which subsets of the real numbers does the number √113 belong? ...
- Math - I was to answer this question: How are the idea of subsets and proper ...

More Related Questions