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anonymous
 5 years ago
Prove: A is a subset of B iff AB= empty set
anonymous
 5 years ago
Prove: A is a subset of B iff AB= empty set

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hi there I am just cracking my head on this proof

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I started but am stuck

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hmm, i'm not the best at formal proofs, but let's see

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0A is a subset of B means that every element of A is an element of B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0then AB is the set of elements in A that don't belong to set B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0but since A is a subset of B, we know that every element of A is an element of B, so that means that there are no elements in A that don't belong to set B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0that's a little confusing can you explain that again?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0we want to know what AB is, or the set of elements in A that don't belong to B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0we started with A is a subset of B, which means that every element of A is an element of B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0right I understand that so far

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so for any element in A, we know that it is also in B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so for any element in A, we know that it is also in B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so we are considering AB, or the set of elements in A that don't belong to B. Let's assume element x is in AB. that means that x is in A, and x is not in B. but we know that can't be true because for any element in A, we know it is in B. so x cannot exist! therefore AB is the empty set.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hey, you still there?
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