## Theorem (proof that) a) A Delta B = AÚ B if A Subscription B

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reza95
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### Theorem (proof that) a) A Delta B = AÚ B if A Subscription B

Theorem (proof that)
a) A Delta B = AÚ B if A Subscription B= Null
b) A Subscription (B Ù C) = (A Subscription B) Ù (A Subscription C)

sorry for bad typing , I got error. better form : http://mathhelpforum.com/discrete-math/ ... post812654
thank you.

stapel_eliz
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Theorem (proof that)
a) A Delta B = AÚ B if A Subscription B= Null
b) A Subscription (B Ù C) = (A Subscription B) Ù (A Subscription C)
What does "Delta" indicate? What does "Ú" mean? What does "Subscription" mean in this context? Does "Null" mean "the empty set"?

What are your thoughts? What have you tried? How far did you get? Where are you stuck?

reza95
Posts: 5
Joined: Fri Mar 07, 2014 3:46 pm
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### Re: Theorem (proof that) a) A Delta B = AÚ B if A Subscripti

I am so sorry , when I want right I get Error and can not submit my post.

Please visit : http://mathhelpforum.com/discrete-math/ ... proof.html
I writing right there.
thank you.

stapel_eliz
Posts: 1628
Joined: Mon Dec 08, 2008 4:22 pm
Contact:
Okay; what does "$\Delta$" mean? What does "Ú" mean? Does "$\phi$" mean "the empty set"?

Seriously: You have to tell people what you mean. And, before anybody can help you get un-stuck, you have to show what you've tried so far.