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## #1 2013-10-21 04:06:53

BlitzBall
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### 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 (2013-10-21 04:08:47)

## #2 2013-10-21 08:30:46

Nehushtan
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### Re: A few questions about subsets.

#### BlitzBall wrote:

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

Why not?

## #3 2013-10-21 20:35:27

bob bundy
Moderator

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### Re: A few questions about subsets.

hi BlitzBall

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

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #4 2013-10-23 05:43:20

BlitzBall
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### Re: A few questions about subsets.

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

## #5 2013-10-23 05:44:24

BlitzBall
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### Re: A few questions about subsets.

#### 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