Theorem aleqd ≪ | index | src | ≫

theorem aleqd (G: wff) {x: nat} (a b: wff x):
  $ G -> (a <-> b) $ >
  $ G -> (A. x a <-> A. x b) $;

Step	Hyp	Ref	Expression
1		aleq	A. x (a <-> b) -> (A. x a <-> A. x b)
2		hyp h	G -> (a <-> b)
3	2	iald	G -> A. x (a <-> b)
4	1, 3	syl	G -> (A. x a <-> A. x b)

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp), axs_pred_calc (ax_gen, ax_4, ax_5)