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## #1 2013-10-20 05:06:53

BlitzBall
Member
Registered: 2012-01-07
Posts: 92

### A few questions about subsets.

Hello all, it has been a long time since. Hope you are all well

Anyway, I have a few questions about empty sets.

Lets take:

T (domain) = {a,b,c,d,e,f}
A = {a,b}
B = {c,d,e,f}

A∧B ⊆ T = is true.

But how is it true? Because A∧B is an empty set, and I always thought an empty set is not a subset of everything "T".

Last edited by BlitzBall (2013-10-20 05:08:47)

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## #2 2013-10-20 09:30:46

Nehushtan
Member
Registered: 2013-03-09
Posts: 905
Website

### Re: A few questions about subsets.

BlitzBall wrote:

I always thought an empty set is not a subset of everything "T".

Why not?

Blog

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## #3 2013-10-20 21:35:27

bob bundy
Registered: 2010-06-20
Posts: 8,137

### Re: A few questions about subsets.

hi BlitzBall

So mathematicians take it that the empty set is a subset of every set.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #4 2013-10-22 06:43:20

BlitzBall
Member
Registered: 2012-01-07
Posts: 92

### Re: A few questions about subsets.

Ahh I see, so that's how it is interpret. I'll remember that. Thanks a lot

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## #5 2013-10-22 06:44:24

BlitzBall
Member
Registered: 2012-01-07
Posts: 92

### Re: A few questions about subsets.

Nehushtan wrote:
BlitzBall wrote:

I always thought an empty set is not a subset of everything "T".

Why not?

Maybe I have forgotten. It has been like 2 years. I wish my memory was long term

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