How would you prove that
(A/B) U B = A if and only if B C A ?
It's the iff that is giving me problems. Is there a technique for this type of proof?
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How would you prove that
(A/B) U B = A if and only if B C A ?
It's the iff that is giving me problems. Is there a technique for this type of proof?
There is no one way to do any set theory proof.Quote:
Originally Posted by Cairo
Here you might note that
Starting withwhat would
This statement is equivalent to the following statement :Quote:
Originally Posted by Cairo
iff
Thanks, but this looks even worse to me!Quote:
Originally Posted by princepsThis statement is equivalent to the following statement :
Would this not be A, Plato?
I was thinking of relabelling (B C A) as D and ((A/B) U B = A) as E and then trying to argue D implies E and also that ~D implies ~E, but not sure if this would work or even where to start.
That is correct. So you have proved it one way.Quote:
Originally Posted by Cairo
Now suppose thatnow show that
Using the distributive law I getQuote:
Originally Posted by PlatoThat is correct. So you have proved it one way.
Now suppose that
(A U B) and (B^c U B) = .......
But not sure how to continue this argument.
Will have a think about it.
Should notQuote:
Originally Posted by PlatoThere is no one way to do any set theory proof.
Here you might note that
Starting with
be
And then be equal to:?