theorem imeq1i (a b c: wff): $ a <-> b $ > $ a -> c <-> b -> c $;
Step | Hyp | Ref | Expression |
1 |
|
id |
(a <-> b) -> (a <-> b) |
2 |
1 |
imeq1d |
(a <-> b) -> (a -> c <-> b -> c) |
3 |
|
hyp h |
a <-> b |
4 |
2, 3 |
ax_mp |
a -> c <-> b -> c |
Axiom use
axs_prop_calc
(ax_1,
ax_2,
ax_3,
ax_mp)