Theorem eor ≪ | index | src | ≫ 

theorem eor (a b c: wff): $ (a -> c) -> (b -> c) -> a \/ b -> c $;
StepHypRefExpression
1 anl 
(a -> c) /\ (b -> c) -> a -> c
2 anr 
(a -> c) /\ (b -> c) -> b -> c
3 1, 2 eord 
(a -> c) /\ (b -> c) -> a \/ b -> c
4 3 exp 
(a -> c) -> (b -> c) -> a \/ b -> c

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp)