Theorem anld ≪ | index | src | ≫ 

theorem anld (a b c: wff): $ a -> b /\ c $ > $ a -> b $;
StepHypRefExpression
1 anl 
b /\ c -> b
2 hyp h 
a -> b /\ c
3 1, 2 syl 
a -> b

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp)