Question

Determine the following. let
U = {1, 2, 3, 4,..., 10}
A = {1, 3, 5, 7}
B = {5, 7, 9, 10}
C = {1, 7, 10}

36.
The number of proper subsets of set A,

Answer 1

can someone explain how to do this?

Answer 2

what are you asking for?

Answer 3

its asking the number of proper subsets of set A
im not sure how to do this problem

Answer 4

so proper would be the ones that are included in the other ones?

Answer 5

Well if a set has x elements, it has 2^x subsets. if you want proper subsets you have to take off one subset.

so for A it would be 2^4-1 = 15 proper subsets

Answer 6

so it would be the elements that are in the other sets?

Answer 7

what does that 36 mean?

Answer 8

it would be like {1}, {1,3} {1,3,5} {3}...... any combination of elements in A

Answer 9

and also in the A subset so it would be
A={1,3,5,7,10} for answer

Answer 10

a subset of A is a set containing some or all of the elements of A as well as the empty set.

To enumerate the subsets of A is a bit tedious.

Answer 11

this is what the question is . polpak..

Answer 12

name the proper subsets of set A

Answer 13

For a short example:
Q = { 1,5,9 }

All the subsets of Q are:
{1,5,9}
{1,5}
{1,9}
{5,9}
{1}
{5}
{9}
{}

Answer 14

The proper ones would just not include the set itself, so in the above example {1,5,9} would not be on the list.

Answer 15

so its whats in the other sets thats part of A

Answer 16

{empty set},{1},{3},{5},{7},{1,3},{1,5},{1,7},{3,5},{3,7},{5,7},{1,3,5},{3,5,7},{1,5,7},{1,3,7},

Answer 17

so its everything that is in EACH set thats a subset?

Answer 18

{1,3,5}
{1,3,7}
{1,5,7}
{3,5,7}
{1,3}
{1,5}
{1,7}
{3,5}
{3.7}
{5,7}
{1}
{3}
{5}
{7}
empty set

Answer 19

If they want the subsets of A you have to list them.

Answer 20

{empty set} does not equal empty set

Answer 21

all combinations of the elements in A

Answer 22

\[\{\} = \emptyset \]

Answer 23

oh you called me a bad word
thats not nice

Answer 24

{1,3,5,7}
{3,5,7}
like this?

Answer 25

Yes, but there's more than that.

Answer 26

yes all the ones we already listed

Answer 27

jhmann, i was trying to help sandi
and you didn't have to be mean to me

Answer 28

yea just put all elements in a subset and then down to {}

Answer 29

nice apology