Simplifying Clause: A' & B' or A & B

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The discussion revolves around simplifying the logical expression (A' or B) and (B' or A) in First Order Predicate Calculus without using parentheses. Participants clarify that A and B are literals, and one suggests that the expression can be rewritten as A <-> B, which is considered a simpler form. Another participant proposes that it could also be expressed as (A and B) or (A' and B'). The conversation highlights the challenge of simplifying expressions with multiple predicates and the application of logical equivalences. Ultimately, the consensus leans towards A <-> B being the simplest representation of the original clause.
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Hi everyone,
how can I simplify this clause to remove parenthesis:

(A' or B) and (B' or A) ?

thanks in advance.

ps: iff is not allowed :frown:
 
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EvLer said:
Hi everyone,
how can I simplify this clause to remove parenthesis:

(A' or B) and (B' or A) ?

thanks in advance.

ps: iff is not allowed :frown:
What are A and B? Is this logic, set theory, probability, ??
 
A and B are "literals" as the book refers to them or n-ary predicates.
Sorry, should have specified: it's First Order Predicate Calculus. This isn't really an excersize. It's just that I saw that logical equivalence
A <=> B
can be rewritten as: (A -> B) and (B -> A);
further, implications (A -> B) are rewritten as: A' or B;
so if i rewrite the logical equivalence i get: (A' or B) and (B' or A)
but i was wondering if it was possible to further simplify this clause :confused:
[edit] i know how to apply distributive laws in cases like this:
(A and B) or C
or similar, but not sure how that might work in clause with 4 predicates [/edit]
 
Last edited:
What do you mean by "simplify"? It seems to me that A <-> B is the simplest form. You could write it as (A and B) or (A' and B')
 
AKG said:
It seems to me that A <-> B is the simplest form. You could write it as (A and B) or (A' and B')
well, just was curios, that's all...

Thanks!
 
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