No problem! I really appreciate all of your help!
But I don't really get what I need to do now
Do I need to start the hypothetical statement with
##(p \equiv q)##
Then start another hypothetical statement with
## ¬((p∧q)∨(¬p∧¬q))##
This? Or
##¬((p∨¬q)∧(¬p∨q))##
This?
So I've set up some truth tables and I was able to find out that I can prove them. But now I am trying an other way. I'm trying to prove
##¬((p∧q)∨(¬p∧¬q)) \to ¬(p \equiv q)##
So I started my hypothetical statement with
##¬((p∧q)∨(¬p∧¬q))##
##¬(p∧q)∧¬(¬p∧¬q)##
Then I started a new hypothetical...
I think that I do understand what you mean and I see that introducing the negation on
##¬(p∧q)∨(¬p∧¬q)##
By doing
##¬((p∧q)∨(¬p∧¬q))→(p≡q)##
##¬((p∧q)∨(¬p∧¬q))→¬(p≡q)##
Is unnecessary because when I use the transposition rule on
##¬((p∧q)∨(¬p∧¬q))→¬(p≡q)##
I get
##(p \equiv q) \to...
I think that we haven't seen the distributive law in logics. I've put all the rules that we have just below. For this exercise we are not allowed to use truth tables, so we have to use these rules to prove it.
##A, B / A∧B ##
##A∧B / A resp. A∧B / B##
##A / A∨B resp. B / A∨B##
##A∨B, A \to C...
Homework Statement
I have to prove that ##(p \equiv q) \equiv ((p ∧ q) ∨ (¬p ∧ ¬q))##
With no premisses
In order to prove this, I first need to prove that:
##(p \equiv q) \to ((p ∧ q) ∨ (¬p ∧ ¬q))##
And:
##((p ∧ q) ∨ (¬p ∧ ¬q)) \to (p \equiv q)##
I was able to find the second implication...