Metamath Proof Explorer


Theorem 2ax6e

Description: We can always find values matching x and y , as long as they are represented by distinct variables. Version of 2ax6elem with a distinct variable constraint. Usage of this theorem is discouraged because it depends on ax-13 . (Contributed by Wolf Lammen, 28-Sep-2018) (Proof shortened by Wolf Lammen, 3-Oct-2023) (New usage is discouraged.)

Ref Expression
Assertion 2ax6e ⊢ ∃ z ∃ w z = x ∧ w = y

Proof

Step Hyp Ref Expression
1 aeveq ⊢ ∀ w w = z → z = x
2 aeveq ⊢ ∀ w w = z → w = y
3 1 2 jca ⊢ ∀ w w = z → z = x ∧ w = y
4 3 19.8ad ⊢ ∀ w w = z → ∃ w z = x ∧ w = y
5 4 19.8ad ⊢ ∀ w w = z → ∃ z ∃ w z = x ∧ w = y
6 2ax6elem ⊢ ¬ ∀ w w = z → ∃ z ∃ w z = x ∧ w = y
7 5 6 pm2.61i ⊢ ∃ z ∃ w z = x ∧ w = y