Theorem syla ≪ | index | src | ≫

theorem syla (a b c d: wff): $ (b -> c) -> d $ > $ a /\ b -> c $ > $ a -> d $;

Step	Hyp	Ref	Expression
1		hyp h1	(b -> c) -> d
2		hyp h2	a /\ b -> c
3	2	exp	a -> b -> c
4	1, 3	syl	a -> d

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp)