Question

the number of proper subsets of A? I don't understand what this question is asking..

Answer 1

A proper subset is a subset, that is not equal to original set

Answer 2

for example if A ={1,2,3}, then {1,2} would be a prope subset, and {1,2,3} would not

Answer 3

okay, but i don't have another set. all it says is the number of proper subsets of A.

Answer 4

oh wait.. it gave me some more info. i'll type it for you to see

Answer 5

a general formula for number of subsets in a set with \(n\) elements is \(2^n\). So the answer to your question is \(2^n-1\), where n is the number of elements in A

Answer 6

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

Answer 7

so.. n=4?

Answer 8

right

Answer 9

\(2^4-1=\)?

Answer 10

15?

Answer 11

right

Answer 12

so that is my answer correct?

Answer 13

yes

Answer 14

thank you for your help.

Answer 15

yw