Theorem zeqmsub2 | index | src |

theorem zeqmsub2 (a b c n: nat):
  $ modZ(n): a -Z b = a -Z c <-> modZ(n): b = c $;
StepHypRefExpression
1 bitr
(modZ(n): a -Z b = a -Z c <-> modZ(n): -uZ b = -uZ c) -> (modZ(n): -uZ b = -uZ c <-> modZ(n): b = c) -> (modZ(n): a -Z b = a -Z c <-> modZ(n): b = c)
2 zeqmadd2
modZ(n): a +Z -uZ b = a +Z -uZ c <-> modZ(n): -uZ b = -uZ c
3 2 conv zsub
modZ(n): a -Z b = a -Z c <-> modZ(n): -uZ b = -uZ c
4 1, 3 ax_mp
(modZ(n): -uZ b = -uZ c <-> modZ(n): b = c) -> (modZ(n): a -Z b = a -Z c <-> modZ(n): b = c)
5 zeqmneg
modZ(n): -uZ b = -uZ c <-> modZ(n): b = c
6 4, 5 ax_mp
modZ(n): a -Z b = a -Z c <-> modZ(n): b = c

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)