Description: Weak form of the Axiom of Transitive Containment using class variables and abbreviations. See ax-tco for more information. (Contributed by Matthew House, 6-Apr-2026)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | axtco2g | |- ( A e. V -> E. x ( A C_ x /\ Tr x ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | axtco1g | |- ( A e. V -> E. x ( A e. x /\ Tr x ) ) |
|
| 2 | trss | |- ( Tr x -> ( A e. x -> A C_ x ) ) |
|
| 3 | 2 | imdistanri | |- ( ( A e. x /\ Tr x ) -> ( A C_ x /\ Tr x ) ) |
| 4 | 3 | eximi | |- ( E. x ( A e. x /\ Tr x ) -> E. x ( A C_ x /\ Tr x ) ) |
| 5 | 1 4 | syl | |- ( A e. V -> E. x ( A C_ x /\ Tr x ) ) |