Theorem lmem1 | index | src |

theorem lmem1 (a b: nat): $ a IN b : 0 <-> a = b $;
StepHypRefExpression
1 bitr
(a IN b : 0 <-> a = b \/ a IN 0) -> (a = b \/ a IN 0 <-> a = b) -> (a IN b : 0 <-> a = b)
2 lmemS
a IN b : 0 <-> a = b \/ a IN 0
3 1, 2 ax_mp
(a = b \/ a IN 0 <-> a = b) -> (a IN b : 0 <-> a = b)
4 bior2
~a IN 0 -> (a = b \/ a IN 0 <-> a = b)
5 lmem0
~a IN 0
6 4, 5 ax_mp
a = b \/ a IN 0 <-> a = b
7 3, 6 ax_mp
a IN b : 0 <-> a = b

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp, itru), axs_pred_calc (ax_gen, ax_4, ax_5, ax_6, ax_7, ax_10, ax_11, ax_12), axs_set (elab, ax_8), axs_the (theid, the0), axs_peano (peano1, peano2, peano5, addeq, muleq, add0, addS, mul0, mulS)