theorem neeq1 (_a1 _a2 b: nat): $ _a1 = _a2 -> (_a1 != b <-> _a2 != b) $;
| Step | Hyp | Ref | Expression |
|---|
| 1 |
|
id |
_a1 = _a2 -> _a1 = _a2 |
| 2 |
1 |
neeq1d |
_a1 = _a2 -> (_a1 != b <-> _a2 != b) |
Axiom use
axs_prop_calc
(ax_1,
ax_2,
ax_3,
ax_mp),
axs_pred_calc
(ax_gen,
ax_4,
ax_5,
ax_6,
ax_7)