Theorem anli ≪ | index | src | ≫ 

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

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp)