Description: Simple relationship between <_ and >_ . (Contributed by David A. Wheeler, 10-May-2015) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | gte-lte | |- ( ( A e. _V /\ B e. _V ) -> ( A >_ B <-> B <_ A ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | df-gte | |- >_ = `' <_ | |
| 2 | 1 | breqi | |- ( A >_ B <-> A `' <_ B ) | 
| 3 | brcnvg | |- ( ( A e. _V /\ B e. _V ) -> ( A `' <_ B <-> B <_ A ) ) | |
| 4 | 2 3 | bitrid | |- ( ( A e. _V /\ B e. _V ) -> ( A >_ B <-> B <_ A ) ) |