Metamath Proof Explorer


Theorem dftrrel3

Description: Alternate definition of the transitive relation predicate. (Contributed by Peter Mazsa, 22-Aug-2021)

Ref Expression
Assertion dftrrel3
|- ( TrRel R <-> ( A. x A. y A. z ( ( x R y /\ y R z ) -> x R z ) /\ Rel R ) )

Proof

Step Hyp Ref Expression
1 dftrrel2
 |-  ( TrRel R <-> ( ( R o. R ) C_ R /\ Rel R ) )
2 cotr
 |-  ( ( R o. R ) C_ R <-> A. x A. y A. z ( ( x R y /\ y R z ) -> x R z ) )
3 2 anbi1i
 |-  ( ( ( R o. R ) C_ R /\ Rel R ) <-> ( A. x A. y A. z ( ( x R y /\ y R z ) -> x R z ) /\ Rel R ) )
4 1 3 bitri
 |-  ( TrRel R <-> ( A. x A. y A. z ( ( x R y /\ y R z ) -> x R z ) /\ Rel R ) )