BaEqvBiBt

f f BaEqvBiBt

Proof:

1
¬f ¬f
2
¬f ≡¬ f
3
¬f ¬ f
4
¬f ¬ f
5
⊢ ¬¬f ≡¬¬ f
4,Prop
6
⊢ ¬¬f f
5, def. of 
7
f f
6, def. of 

qed

2023-09-12
Contact | Home | ITL home | Course | Proofs | Algebra | FL
© 1996-2023