The Logic Resource Center
Public Alpha
Systems
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Systems
The Logic Resource Center
Public Alpha
Systems
Open options
Systems
Double Negation
Constants
~
Systems
The Logic Book
Start a Problem
→
Double Negation
i.
ϕ
ii.
~
~
ϕ
DN: i
i.
~
~
ϕ
ii.
ϕ
DN: i
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derivation type in the
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