Theorem zeqmeqm23d | index | src |

theorem zeqmeqm23d (G: wff) (a b c d n: nat):
  $ G -> modZ(n): a = b $ >
  $ G -> modZ(n): c = d $ >
  $ G -> (modZ(n): a = c <-> modZ(n): b = d) $;
StepHypRefExpression
1 zeqmtr
modZ(n): b = a -> modZ(n): a = d -> modZ(n): b = d
2 zeqmcom
modZ(n): a = b -> modZ(n): b = a
3 hyp h1
G -> modZ(n): a = b
4 3 anwl
G /\ modZ(n): a = c -> modZ(n): a = b
5 2, 4 syl
G /\ modZ(n): a = c -> modZ(n): b = a
6 zeqmtr
modZ(n): a = c -> modZ(n): c = d -> modZ(n): a = d
7 anr
G /\ modZ(n): a = c -> modZ(n): a = c
8 hyp h2
G -> modZ(n): c = d
9 8 anwl
G /\ modZ(n): a = c -> modZ(n): c = d
10 6, 7, 9 sylc
G /\ modZ(n): a = c -> modZ(n): a = d
11 1, 5, 10 sylc
G /\ modZ(n): a = c -> modZ(n): b = d
12 zeqmtr
modZ(n): a = b -> modZ(n): b = c -> modZ(n): a = c
13 3 anwl
G /\ modZ(n): b = d -> modZ(n): a = b
14 zeqmtr
modZ(n): b = d -> modZ(n): d = c -> modZ(n): b = c
15 anr
G /\ modZ(n): b = d -> modZ(n): b = d
16 zeqmcom
modZ(n): c = d -> modZ(n): d = c
17 8 anwl
G /\ modZ(n): b = d -> modZ(n): c = d
18 16, 17 syl
G /\ modZ(n): b = d -> modZ(n): d = c
19 14, 15, 18 sylc
G /\ modZ(n): b = d -> modZ(n): b = c
20 12, 13, 19 sylc
G /\ modZ(n): b = d -> modZ(n): a = c
21 11, 20 ibida
G -> (modZ(n): a = c <-> modZ(n): b = d)

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)