Theorem negimp_splitr_neg ≪ | index | src | ≫

\neg\imp右拆分\neg

theorem negimp_splitr_neg (A B: wff): $ \neg (A \imp B) \imp \neg B $;

Step	Hyp	Ref	Expression
1		imp_introrev_neg	(B \imp A \imp B) \imp \neg (A \imp B) \imp \neg B
2		introl_imp	B \imp A \imp B
3	1, 2	ax_mp	\neg (A \imp B) \imp \neg B

Axiom use

Logic (ax_mp, ax_1, ax_2, ax_3)