Theorem lteq2d ≪ | index | src | ≫

theorem lteq2d (_G: wff) (a _b1 _b2: nat):
  $ _G -> _b1 = _b2 $ >
  $ _G -> (a < _b1 <-> a < _b2) $;

Step	Hyp	Ref	Expression
1		eqidd	_G -> a = a
2		hyp _h	_G -> _b1 = _b2
3	1, 2	lteqd	_G -> (a < _b1 <-> a < _b2)

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), axs_peano (peano2, addeq)