Theorem elxabe | index | src |

theorem elxabe (A: set) (a b: nat) (p: wff) {x: nat} (B: set x):
  $ x = a -> (b e. B <-> p) $ >
  $ a, b e. X\ x e. A, B <-> a e. A /\ p $;
StepHypRefExpression
1 hyp h
x = a -> (b e. B <-> p)
2 1 anwr
T. /\ x = a -> (b e. B <-> p)
3 2 elxabed
T. -> (a, b e. X\ x e. A, B <-> a e. A /\ p)
4 3 trud
a, b e. X\ x e. A, B <-> a e. A /\ p

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)