Description: Binary relation form of OutsideOf . Theorem 6.4 of Schwabhauser p. 43. (Contributed by Scott Fenton, 17-Oct-2013) (Revised by Mario Carneiro, 19-Apr-2014)
Ref | Expression | ||
---|---|---|---|
Assertion | broutsideof |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-outsideof | ||
2 | 1 | breqi | |
3 | brdif | ||
4 | 2 3 | bitri |