Metamath Proof Explorer


Theorem reldmran

Description: The domain of Ran is a relation. (Contributed by Zhi Wang, 4-Nov-2025)

Ref Expression
Assertion reldmran
|- Rel dom Ran

Proof

Step Hyp Ref Expression
1 df-ran
 |-  Ran = ( p e. ( _V X. _V ) , e e. _V |-> [_ ( 1st ` p ) / c ]_ [_ ( 2nd ` p ) / d ]_ ( f e. ( c Func d ) , x e. ( c Func e ) |-> ( ( oppFunc ` ( <. d , e >. -o.F f ) ) ( ( oppCat ` ( d FuncCat e ) ) UP ( oppCat ` ( c FuncCat e ) ) ) x ) ) )
2 1 reldmmpo
 |-  Rel dom Ran