Theorem sapp01 | index | src |

theorem sapp01 (a: nat): $ 0 @@ a == 0 $;
StepHypRefExpression
1 eq0al
0 @@ a == 0 <-> A. x ~x e. 0 @@ a
2 eleq1
fst x, snd x = x -> (fst x, snd x e. 0 @@ a <-> x e. 0 @@ a)
3 fstsnd
fst x, snd x = x
4 2, 3 ax_mp
fst x, snd x e. 0 @@ a <-> x e. 0 @@ a
5 prelsapp
fst x, snd x e. 0 @@ a <-> (a, fst x), snd x e. 0
6 el02
~(a, fst x), snd x e. 0
7 5, 6 mtbir
~fst x, snd x e. 0 @@ a
8 4, 7 mtbi
~x e. 0 @@ a
9 8 ax_gen
A. x ~x e. 0 @@ a
10 1, 9 mpbir
0 @@ a == 0

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)