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## Main Question or Discussion Point

I have ~(P&Q) and I want to get ~P v ~Q

(& means and)

(v means or)

Am I right in thinking that I can:

1.~(P&Q) Main assumption

Sub derivation

2..Assume P&Q

3.Reiterate ~(P&Q)

End sub derivation

4.Then do 1-2, ~I (negation elimination) to get ~P

5.then do vI (disjunction introduction) (to number 4) to get ~P v ~Q

I'm confused on how exactly to extract ~P from the negation ~(P&Q). My text book completely ignores it.

Is my method correct?

(Mods I didn't know where to put this. I'm thinking it isn't here)

(& means and)

(v means or)

Am I right in thinking that I can:

1.~(P&Q) Main assumption

Sub derivation

2..Assume P&Q

3.Reiterate ~(P&Q)

End sub derivation

4.Then do 1-2, ~I (negation elimination) to get ~P

5.then do vI (disjunction introduction) (to number 4) to get ~P v ~Q

I'm confused on how exactly to extract ~P from the negation ~(P&Q). My text book completely ignores it.

Is my method correct?

(Mods I didn't know where to put this. I'm thinking it isn't here)

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