Metamath Proof Explorer


Theorem ineccnvmo2

Description: Equivalence of a double universal quantification restricted to the range and an "at most one" inside a universal quantification. (Contributed by Peter Mazsa, 4-Sep-2021)

Ref Expression
Assertion ineccnvmo2
|- ( A. x e. ran F A. y e. ran F ( x = y \/ ( [ x ] `' F i^i [ y ] `' F ) = (/) ) <-> A. u E* x u F x )

Proof

Step Hyp Ref Expression
1 ineccnvmo
 |-  ( A. x e. ran F A. y e. ran F ( x = y \/ ( [ x ] `' F i^i [ y ] `' F ) = (/) ) <-> A. u E* x e. ran F u F x )
2 alrmomorn
 |-  ( A. u E* x e. ran F u F x <-> A. u E* x u F x )
3 1 2 bitri
 |-  ( A. x e. ran F A. y e. ran F ( x = y \/ ( [ x ] `' F i^i [ y ] `' F ) = (/) ) <-> A. u E* x u F x )